Livestock’s Long Shadow


A link to the World Health Organization’s FAO paper on the effects of our dietary choices on the environment seems timely, given recent weather related disasters brought on by climate change. It’s late in the game to make an impact, but it is not too late.

https://www.fao.org/3/a0701e/a0701e00.htm

What did our ancestors eat?


To put it bluntly, it’s irrelevant. Why? Because humans are still evolving. If our evolution had come to a halt over ten thousand years ago, before agriculture was invented, then, yes, our ancestral diet might still matter. Agriculture, however, has changed many things, including our genome (Carmody et al, 2016).

Prior to the onset of agriculture, humans, like every other animal in existence, then and now, were lactose intolerant. Keeping farm animals changed this. While some populations (such as Chinese, Pima, Bantu) are still, to various extents, lactose intolerant, most of us have developed the ability to digest milk, a feat that ensured the survival of several pastoral societies around the globe.

Adaptations for extracting sugar from starchy foods vary among populations, as differences in environment and agricultural habits led to the evolution of a number of genetic variations (Hardy et al. 2015) (Perry et al. 2007). These differences mean that some populations are better adapted to consuming and thriving on plant foods, while a small segment are better adapted for consuming animal products. The latter tend to reside in places such as Siberia, where vegetation is scarce.

For most of us, modern, post-agriculture humans, consuming animal products on a regular basis can raise the risk of some health problems (heart disease, certain types of cancer, type two diabetes). This is particularly true for populations better adapted to plant based diets, such as Eastern Europeans, who, ironically, have a love affair with meat based cuisine, and sport some of the highest cardiovascular disease rates in the world.

Gut bacteria changes, antibodies against neu5gc found in red meat (dubbed the meat eater’s molecule), the development of smaller jaws, alcohol consumption, and countless other adaptations to stationary, agricultural life have all taken place in very recent human history. As such, the best way to determine which dietary habits are worth keeping and which are to be discarded, is to look at the current human genome, while taking into account geographical differences, rather than casting our eyes to the past and dwelling on our ancestors’ choices.

Can cooking temperatures transform cooking oils into trans fats?


Not really.

Trans fats form under temperatures much higher than those reached while cooking. While some trans fat formation may occur during cooking, it is too modest to be of any significance. To put things in perspective, the use of very high heat in cooking may yield an increase in trans fats of roughly 3%, whereas, industrial hydrogenation (which uses a catalyst, in addition to high heat) will yield 25% to 45%.

References:

Dobarganes C, Márquez-Ruiz G. Possible adverse effects of frying with vegetable oils. British Journal of Nutrition. 2015;113(S2):S49-S57.

Przybylski R, Aladedunye FA. Formation of Trans fats: during food preparation. Canadian Journal of Dietetic Practice and Research. 2012;73(2):98-101.

Will B vitamins give you an energy boost?


Yes, say naturopaths, supplements pushers and people operating under the placebo effect, but the evidence is just not there.

B vitamins (B1, B2, B3, B6, B9 and B12) play a role in metabolism, specifically, they are cofactors that help convert calories into ATP (adenoosine triphosphate). The words “calorie” and “energy” are used interchangeably, creating confusion among consumers who interpret the word “energy” to mean “energy levels” or ” “liveliness”. In this instance, however, “energy” simply means “fuel”.

Western dietary habits, for all their downsides, do, generally, provide enough B vitamins on a daily basis to sustain normal metabolic processes. This means that, unless there is a B vitamin deficiency present, supplementing will not have any effect. The extra vitamins will be excreted in urine.

If a deficiency is present, supplementation will address it, but will not provide an energy boost. Real deficiencies will result in decreased performance, particularly in athletes. Supplementing to correct deficiency status will bring performance back to normal levels, but will not enhance it, or boost it.

Any perceived added liveliness in the wake of taking B vitamin supplements is a placebo effect, likely derived from following the advice of a health provider who appears to be knowledgeable and an authority on the subject, but is, in fact, nothing of the kind (read: a naturopath / chiropractor / insert any other self appointed “specialist” here).

So, save your money and get active. The more you move, the more vibrant you will feel, and you won’t have to spend a dime.

References:

Huskisson E., Maggini S, Ruf M. Vitamins and Minerals in Fatigue, The Journal of International Medical Research, 2007; 35: 277-289.

Krause’s Food – the Nutrition Care Process (Krause’s Food & Nutrition Therapy), 2016.

“Stuffed” book review


I recently re-read a review I wrote on “Stuffed”, a book that critiques the roles industry and governments play in the obesity epidemic, and one that has come up a few times in discussions with my students recently. I’m sharing it, in an attempt to get myself back in the blogging habit. 😊 The references are a little outdated, but still stand (though, I will refresh them a bit over the next few days).

A food industry insider, Hank Cardello laments the role corporations play in expanding America’s collective girth.  His book portrays consumers as being virtually helpless in the face of corporate marketing ploys and failed government attempts to make Americans healthier.  While he excuses corporate behavior as being necessary in order to stay profitable, he admonishes the government for taking on a regulatory role.  Cardello is self-admittedly against government regulation of the food industry, except in terms of overseeing food safety issues such as Mad Cow and E coli.

Beyond making sure our food is safe to eat, he sees no need for government to be involved in matters of nutrition.

With few exceptions, Cardello doesn’t tell us much that is surprising.  He fills more than two thirds of his book with detailed descriptions of marketing ploys, advertising tricks (on the airways, in print, and in America’s stores and restaurants), and a running campaign against government control over virtually all things food industry related.  Statistics are scarce, and when they do show up, they are generally presented with lightly veiled bias.

For instance, in an effort to place some of the blame on sugar consumption, Cardello cites these comparative statistics: “in the 1950s” he says, “kids drank three cups of milk for every cup of soda. Today, the ratio is reversed. Think of the overall impact: a typical 12-ounce can of soda is 10 percent sugar, or ten teaspoons. Three sodas are almost 450 calories of sugar. The typical American drinks a gallon of soda every week” (1).

Shocking indeed.  That is, until we look more carefully at the details.  First off, he equates drinking three cups of soda with three cans of the same.  Second, one cup of milk in the 1950’s meant a cup of whole milk.  According to the USDA nutrient database for standard reference, one cup of whole milk has 149 calories, 4.55 grams of saturated fat, and 13 grams of sugar (2).  Thus,

3 cups of milk + 1 cup of soda = 597 calories, 62 grams of sugar, 13.65 grams of saturated fat

3 cups of soda + 1 one cup of milk = 599 calories, 82 grams of sugar, 4.55 grams of saturated fat

The difference in sugar content is overshadowed by the saturated fat content of whole milk.

A chapter dedicated to explaining how larger portions increase profits for retail and restaurant businesses is, perhaps, one of the book’s most interesting eye openers.  Cardello explains: “If I make my muffins bigger, my ingredient costs go up, but not as much as the price I can charge. Therefore I make a higher profit with the larger size. Same holds for french fries. Same holds for beverages” (1). He points out that the same is true of combo meals.  While a combo meal saves the consumer some money per item, the consumer often ends up purchasing more items than s/he would have otherwise, and, thus, s/he ends up spending more.  After all, why buy just a burger and a drink when a combo is available that also includes fries, for just a dollar more?

All you can eat buffets operate much in the same way and are, perhaps, more dangerous in terms of calories consumed because, unlike a meal at a fast food or conventional restaurant, “doggie bags” are not part of the deal.  The patron must consume all the food included in the seemingly reasonable price right on the spot.  To eat any less leaves the consumer feeling s/he did not get “a deal”.  Overeating, in such an environment, is almost inevitable.

Cardello’s anti-government bias permeates the pages of “Stuffed”.  He points out errors in some government regulation attempts and concludes the government should play no role at all in helping Americans achieve healthier nutrition status as a result.  This is illogical at best.  Programs (government run or otherwise) that don’t work can be adjusted or replaced with programs that are beneficial.  He states: “In the last fifty years, the failures of federal, state, and local governments in the United States to create a workable guidance and regulatory system have played an important role in making Americans fatter” (1). To support his opinion of government inadequacy, Cardello sometimes uses outrageous examples as if they are the law of the land:  “The height of ludicrous government behavior perhaps revealed itself in Mississippi, when there was a proposal to refuse service to obese people in restaurants. Who’s going to be the arbiter of fat in the obviously panicky Magnolia State?” (1).

Taxation of empty calorie, artery clogging, fat laden foods is not something Cardello wants to see.  He views the “sin tax” as being useless.  But is it?  When independent research surpassed that of the tobacco industry and  showed the public once and for all that tobacco use significantly raises the risk of lung cancer, emphysema, and CVD, the government took notice.  Since their implementation over a decade ago, the sin taxes on tobacco products have played an important role in significantly lowering consumption rates (3).  As cigarette prices went up, consumption went down. This, of course, may be a coincidence, but the trend has continued to date.

<<<<<<<<
g with this mindset, Cardello asks: “Have we witnessed any government programs and regulations that have proven to lower the rates of obesity in this country?”

Uhm… yes.

At the local level, programs overlooking school lunches in several communities have had great results (4).  Five elementary schools in Osceola County, Florida, participated in a two year nutrition education program which integrated nutrition, physical activity, and lifestyle education curricula in an effort to help kids learn how to eat healthier foods and keep their weight in check.  The results were significant, particularly in light of the fact that the school could only control food intake during lunch and snack time, having no control over what the kids would eat when off the school grounds.  Blood pressure improved significantly and overall weight and body mass index improved considerably (5).  This is one example of a public school program that, should it be implemented permanently, can have beneficial results.

Cardello provides some unexpected, and perhaps counterintuitive, solutions in his concluding chapters.  Although he places the blame for America’s weight problems mainly on the food industry’s lack of concern for consumer health, Cardello insists that it is the industry itself that must fix the problem, not the government, and surely not the consumers.

He envisions a future when people can eat whatever they want and will not have to worry about calories, fat content, and climbing cholesterol levels.  He sees GMOs, modified fats and artificial sweeteners as the answer to all of America’s weight problems.

While I share the author's enthusiasm for GMOs, I can't say the same for sweeteners and fats. Zero calorie drinks seem to be the author's favorite solution, in spite of questionable effects they may have in terms of longterm weight management.  Recent research has shown that the body "keeps track" of nutrients and the calories they provide through the use of sensors along the GI tract.  When repeatedly presented with a zero calorie beverage, which the body expects to have a caloric value (nothing in nature tastes sweet but has zero calories), over the longterm, the mechanism which keeps track of energy intake becomes “confused”, for lack of a better word.  This disruption appears to negatively impacts appetite and weight regulation, though, more research is needed to identify the mechanism of action (7, 8).

Cardello admits that artificial replacements of problem foods can create more problems: "Among the frying oils fast replacing them is what’s known as interesterified (IE) oils. While devoid of trans fats, these new oils may help create a new demon. Recent research by K. C. Hayes, the noted expert on fats at Brandeis University, reported in Nutrition and Metabolism, that IE oils resulted in elevated fasting glucose levels and reduced insulin values compared with naturally structured fats. In fact, according to his study, they were even worse than the partially hydrogenated (high–trans fat) oils they replaced." (1) At the same time, he proposes these kinds of ingredients as the solution to America’s weight management problem. He calls their inclusion in the food supply without much fanfare “Stealth Health”.

Cardello may have lost all faith in the consumer, but, these days, people are paying more attention to ingredients and the quality of the foods they eat than ever before.  The problem is they’re being duped by corporate advertising and the kinds of marketing tactics he describes.

Although an informative and entertaining read, Cardello’s “Stuffed” fizzles out in the end.  His so-called solutions to the problem risk becoming problems themselves.

References

1. Cardello H. Stuffed: An Insider's Look at Who's (Really) Making America Fat. Ecco. 2009

2. USDA Agricultural Research Service Nutrient Data Laboratory http://www.nal.usda.gov/fnic/foodcomp/search/ Accessed on July 10, 2010.

3. Orzechowski, Walker. The Tax Burden. 2007

4. Belkin L.  The school lunch test.  New York Times. 2006, August 20.

5. Hollar D, Messiah SE, Lopez-Mitnik G, Hollar TL, Almon M, Agatston AS. Healthier options for public schoolchildren program improves weight and blood pressure in 6- to 13-year-olds. University of Miami Miller School of Medicine, Miami, FL.  J Am Diet Assoc. 2010; 110(2):261-7.

6. Biing-Hwan L.  Healthy Eating Index, USDA Economic Research Service, Agriculture Information Bulletin Number 796-3, U.S. Department of Agriculture. 2005

7. Swithers SE,  Davidson TL. A Role for Sweet Taste: Calorie Predictive Relations in Energy Regulation by Rats. Behavioral Neuroscience. 2008; 122: 1

8. Fowler SP. Abstract 1058-P presented at the 65th Annual Scientific Sessions of the American Diabetes Association, San Diego. 2005, June 10-14.

Fasting – is that what you’re really doing?


Run a search on the word “fasting” and you will undoubtedly get back hundreds of results, most of which will lead you to websites loaded with a mix of information ranging from half truths to excursions into the absurd.  So, what’s the deal with fasting?  Is it good, bad, or somewhere in between?

The fasting state

Abstinence from food for 18 to 48 hours is called the “fasting state” (1). During the fasting state, glycogen (stored carbohydrate) is depleted and amino acids from muscle protein break down to provide fuel for gluconeogenesis (production of glucose by the liver in the absence of carbohydrate intake) and the body enters a state of ketosis.  (If you thought only low carb diets promoted ketosis, you may want to look at fasting and starvation as something a bit more extreme than low-carb, in that they are both “no-carb”.) Large amounts of nitrogen are lost through urine to keep up with the body’s high rate of muscle protein breakdown and glucose synthesis by the liver (1).

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The starvation state

Abstinence from food for more than 48 hours is called the “starvation state” (1).  While a 24 hour fast is generally a good idea every now and then, starving oneself is not.  So, to be clear:  if you’re abstaining from food for more than 48 hours you are not fasting – you are starving your body of important nutrients.

When fasting turns into starvation, fat stores become the main suppliers of energy as the body tries to hang on to important proteins (enzymes, antibodies, hemoglobin).  Fatty acid levels in the blood increase sharply and the brain and skeletal muscles adapt to using ketones for energy.  The more fat deposits a person has, the longer s/he can survive – in theory.  In practice, the detrimental effects of starvation on the immune system leave people susceptible to infections which, in the absence of protein in the diet, can lead to death.

Purposeful starvation

Most people undertaking a fast, do so for more than 48 hours, which means they are actually engaging in starvation.  On purpose.  I don’t know how long such people keep up this feat, but I suspect most do not run out of fat stores by the time they start eating again.  Thus, they are in no danger of starving to death.  However, there are side effects to starving oneself.

Fasting and starvation rob the body of essential amino acids (EAA), essential fatty acids (EFA), and essential vitamins and minerals (1).  They’re called “essential” for a reason.  We can not produce them ourselves, so, we must get them from food.  If you think you can overcome this problem by juicing while you’re abstaining from food, I hope to relieve you of such fantasies in the next sections.

Juicing

Juicing entails the removal of pulp and nutrient rich skins from fruits and vegetables. As a result, some essential vitamins and minerals, as well as most of the fibre are lost.  This is no big deal if you enjoy the products of juicing as part of an adequate diet, but if you are relying on juice to get you all the nutrients your body needs as you forego solid foods, you are far from reaching your goal.

Protein intake is significantly limited, meaning you’re very likely to experience the side effects of continuously robbing your body of essential amino acids.  I use the word “likely” because, in theory, if you consume enough juice, you will eventually meet your EAA needs.  In practice, this is virtually impossible, since the amount of juice needed would be of astronomical proportions.  Limiting amino acids, particularly lysine, methionine and tryptophan would keep your body from producing adequate amounts of proteins (antibodies, enzymes, hormones, etc.).  The longer you keep it up, the longer your body has to make do with robbing muscles of their proteins to compensate for self-imposed limitations.

Leptin

Our stomachs and adipose cells under the skin secrete a hormone called leptin.  Its job is to keep track of how much fat we store and to suppress appetite after eating by stimulating the release of melanocyte stimulating hormone (MHS) (1).  In addition, leptin alters immune system function.  Fasting decreases basal leptin levels in the body.  Since inducing starvation in human subjects is considered unethical, we can only extrapolate what happens to starving people based on animal models and the study of malnourished persons or those suffering from eating disorders such as anorexia nervosa (2,3).  The effects of leptin imbalances during fasting and starvation are visible in as little as two days in animal models, with immune system suppression occurring at just 48 hours (4).  It should come as no surprise if, during a bout of starvation (water “fasts”) or adhering to a liquid diet yielding inadequate essential nutrients (particularly protein), people succumb to viral, bacterial or fungal infections, among other things.  All it takes is to be in the right place at the right time (in other words, exposure).

Other stuff

In a surprising turn of events, researchers in Israel found that some of their initially obese test subjects, who had no prior diabetic symptoms, developed diabetes after a course of very low calorie dieting (5).  This may have been the result of insulin resistance which usually occurs during early stages of starvation.  The subjects were not starving, but the low caloric intake may have mimicked starvation enough to lead to insulin resistance.

One day fasts and alternate day fasting

This I can support.  There is a fair amount of evidence that one day fasts and alternate day fasting have a number of benefits ranging from weight loss and maintenance to decreased risk of some cancers and cardiovascular disease (see my post on caloric restriction).  Although the most likely to be beneficial, alternate day fasting is the toughest of the two in terms of adherence.  Most people get tired of it within a week or two, many much sooner.  Alternate day fasting results in lowered caloric intake which, as I mentioned in a previous post, has been linked to higher quality of life and possibly longevity.

Finally…

If you’re abstaining from food for more than two days, you are not fasting. You are starving.  I suggest you stop.  If you are engaging in one day fasts or alternate day fasts, more power to you.  If you think juicing while fasting or starving is enough to keep all bodily functions operating properly, you are kidding yourself.  Juicing is the equivalent of a very low calorie diet which is to say, you’re not getting essential nutrients and you’re setting yourself up for infections, weight re-gain after the regimen is over and possibly other issues not readily visible.

I did not touch on the claim that fasts of any kind or starvation of any length act as a way to detoxify the body or liver because I already covered it here.

References

  1. Gropper SS, Smith JL, Groff JL.  Advanced Nutrition and Human Metabolism, 5th Ed. CA: Wadsworth; 2009.
  2. Marcos A, Varela P, Toro O, Lopez I, Nova E, Madruga D, Casas J, Morande G.  Interactions between nutrition and immunity in anorexia nervosa: a 1 year follow-up study.  Am J Clin Nutr, 1997;66(2):485S-490S.
  3. Lord GM, Matarese G, Howard JK, Baker RJ, Bloom SR, Lechler RI. Leptin modulates the T-cell immune response and reverses starvation-induced immunosuppression. Nature 1998;394:897–901.
  4. Faggioni R, Moser A, Feingold KR, Grunfeld C. Reduced leptin levels in starvation increase susceptibility to endotoxic shock. Am J Pathol, 2000;156(5): 1781-1787.
  5. Koffler M, Kisch ES.  Starvation diet and very low calorie diets may induce insulin resistance and overt diabetes mellitus. J Diabetes Complications, 1996;10(2):109-12.

The skinny on healthy skin


Your skin is your largest organ.  On average, this amounts to about 2 square meters of surface and roughly 3 to 4 kilograms of mass. It helps protect you against potentially harmful substances, extreme temperatures and the Sun’s ultraviolet light. In turn, the skin’s three layers – the epidermis, dermis, and subcutis – depend on you to keep them healthy.  This means taking precautions to avoid the Sun’s damage and meeting your nutritional requirements on a regular basis.

Eat right

Aside from scheduling regular visits to the dermatologist, avoiding direct Sun light for extended periods of time, and wearing Sun screens (hats, long sleeves, umbrellas, lotions), you can make sure you consume a healthy diet which includes vitamins A, B, C, E and omega-3 fatty acids.

Vitamin A

Vitamin A refers to three compounds (retinol, aldehyde, and retinoic acid) called retinoids.  Plants contain carotenoids which are metabolized by the body to form retinoids, the most important of which is B-carotene.  About 50% to 80% of vitamin A in the body is stored in the liver.  The rest is spread out among the lungs, kidneys, adipose tissue and a number of specialized cells throughout the body (1).

Known by most people as being crucial for good vision, vitamin A also plays a role in cell function, growth, development and differentiation (and, thus, is important in keeping our skin healthy), immune function, reproduction and a number of systemic functions, such as gene expression.

The RDA for adults is 700-900 RAE (retinol activity equivalents) which translates into 700-900 mcg of retinol or 8,400-10,800 mcg of B-carotene per day, depending on gender and pregnancy status (1).

  • 1 small sweet potato = 7,374 RAE (about ten times the RDA, or 88,488 mcg of B-carotene)
  • 1 cup raw carrots = 5,553 RAE
  • 1 cup of cooked broccoli = 725 RAE
  • 2 medium tomatoes = 860 RAE
  • 1 cup cooked spinach = 6,882 RAE
  • 1 cup cantaloupe = 1,625 RAE

Given the abundance of carotenoids in the plant world, particularly in the orange and red fruits and vegetables category, it is relatively easy to meet our daily requirements.

Supplementation with vitamin A is contraindicated in the absence of a known deficiency and without medical supervision.  Although readily available in our food supply, vitamin A may be poorly absorbed by some individuals who suffer from pancreatic or liver disease or who lack fat and/or zinc in their diets. On the flip side, vitamin A toxicity is serious business. Regular consumption of vitamin A at 100 times or more the RDA may lead to liver disease, skin disorders, higher incidence of bone fractures (including hip) and lung cancer among smokers (1).

B vitamins

B vitamins, in particular niacin, help keep skin healthy.  Niacin is essential for energy production and metabolism.

Niacin in most plants and grains is covalently bound with peptides and carbohydrates that are not released during digestion. However, alkaline hydrolysis (the addition of water and alkali) makes niacin bioavailable (the Central American tradition of soaking grains in lime water before cooking is, thus, more than just a dietary preference as it serves an important purpose). Niacin is also synthesized from tryptophan (an essential amino acid) with moderate efficiency (60 mg of tryptophan yield 1 mg of niacin) (1).

Ready to eat cereals have the highest niacin content (up to 26 mg per serving, depending on brand).  Mushrooms, peanuts, coffee, breads and pasta all yield enough niacin to meet daily recommendations from just one serving.  Current DRI for adults is anywhere from 2 – 18 mg depending on age and gender (1).

Vitamin C

Vitamin C, aka ascorbic acid, is involved in many electron transport reactions, some of which are involved in collagen synthesis.  Collagen is a fibrous protein found primarily in connective tissue, cartilage, bone, teeth, skin and tendons.  Needless to say, it is important for maintaining healthy skin.  Lucky for us, vitamin C is abundant in most fruits and vegetables, making it relatively easy to meet daily requirements (15 to 120 mg per day depending on age and gender)(1).  In spite of this, vitamin C is one of the most commonly overconsumed supplements in the US and Canada. I can only guess that its popularity rests with the misguided belief that it prevents or cures the common cold.

Too much of this good thing may result in GI disturbances, an increased risk of some cancers (whereas, normal intake has the opposite effect), slight oxaluria, and false-positive urinary glucose test results (1).

Vitamin E

Vitamin E is the most important fat soluble antioxidant in the cell as it protects cell membranes from free radical activity.  It depends on other nutrients and enzymes to do its job, particularly copper, zinc, riboflavin and manganese.

Vitamin E is measured in terms of a-tocopherol equivalents (a-TE) of which adults need about 15 mg per day.

Tocopherols (and tocotrienols) are only synthesized in plants.  The average American, and to a lesser extent, the average Canadian, consumes most of his/her vitamin E in the form of vegetable oil even though healthier sources abound.  One ounce of almonds yields a whopping 7.33 mg (more than three times the amount found in one tablespoon of canola oil)(1).

Omega-3 fatty acids

There are three types of omega-3 fatty acids:  a-linolenic acid (ALA), eicosapentaenoic acid (EPA), and docosahexanoic acid (DHA).  Of these, ALA is an essential fatty acid (EFA), meaning it can not be synthesized by the human body, so, we must get it from food. Humans can desaturate and elongate ALA into EPA and DHA as needed, thus, it is important to include ALA in the diet on a regular basis (1).

The conversion rate of ALA to EPA and DHA is relatively low in persons who consume fish.  However, in vegetarians and vegans, the conversion rate is significantly higher, which explains the similarity of EPA and DHA levels between these groups and their meat-eating cohorts (2).  It is not necessary for vegetarians or vegans to supplement with EPA and DHA as long as they consume a healthy diet that meets their nutritional needs.  In all groups, conversion rates of ALA to EPA and DHA are higher in women (3).

EFA deficiency is rare and occurs primarily among newborns and infants.  Even in developing countries, where food is scarce, EFA deficiency is very low most likely because the most commonly consumed type of fat in such areas is usually vegetable based (vegetable fat is a good source of ALA)(4).

Water

Lastly, stay hydrated inside and out.  Rather than smother your skin with lotion (which can actually draw moisture out of the skin), use a water bottle set on “mist” instead.  Obviously, this may not be the thing to do at the office, but while you’re outdoors or at home, opt for water.  It doesn’t cost anything and it is better for your skin than most other topical applications.

REFERENCES

  1. Mahan LK, Escott-Stump S. Krause’s Food and Nutrition Therapy. MO: Saunders-Elsevier; 2008.
  2. Welch AA, Shakya-Shrestha S, Lentjes MAH, Wareham NJ, Khaw KT. Dietary intake and status of n-3 polyunsaturated fatty acids in a population of fish-eating and non-fish-eating meat-eaters, vegetarians, and vegans and the precursor-product ratio of a-linolenic acid to long-chain n-3 polyunsaturated fatty acids: results from the EPIC-Norfolk cohort. Am J Clin Nutr, 2010;92:1040-51.
  3. Burdge GC. Metabolism of a-linolenic acid in humans. Prostaglandins, leukotrienes and essential fatty acids, 2006;75(3):161-8.
  4. The Merck Manual for Health Care Professionals. Available at: http://www.merckmanuals.com/professional/nutritional_disorders/undernutrition/essential_fatty_acid_deficiency.html  Accessed: August 9, 2012.

The role of exercise in weight loss


Regular exercise can help lower the risk of cardiovascular disease, improve bone density and muscle tone, maintain a healthy weight, improve hemoglobin A1c levels, work wonders against psychological stress and anxiety, lessen arthritis pain and lower the risk of Alzheimer’s disease (1,2,3,4).  It will not, however, make you lose weight (5).

Surprised?

You shouldn’t be.  Think about it:  you can consume 500 calories (a slice of cheesecake or a 10 oz Margarita) in just a few minutes, but it takes an adult of 150 lbs over two hours of fast paced walking, or over one hour of vigorous running, to burn the same amount (1).  If you wish to burn more than 500 calories, to lose weight (as opposed to simply burning off the added calories), it will take an additional hour or so to create the desired negative balance. If the Margarita and the cheesecake slice were both a part of your after dinner indulgence, you’re looking at over 1,000 calories (making up half the daily caloric requirement for most healthy adults) that you must make disappear just to maintain your current weight.

In other words, you can’t outrun your mouth.  Or, to be fair, you can’t outrun your mouth if you have a life which includes a job, commute to work, a household to maintain, child care or other such activities as part of your daily routine.  There simply isn’t enough time in the day to compensate (with exercise) for added calories.  Maybe you can pull it off once in a while but most of the time, it’s a bit of a stretch.

If you have a reasonably healthy body mass index (BMI), regular exercise, which includes endurance as well as weight bearing activities, will go a long way toward keeping all your bits and parts in tip-top shape and your weight in a healthy range.  You will also run a significantly lower risk of gaining unwanted pounds.

You may be wondering:  if regular exercise can have such a positive effect on the body, why even mention that it falls short in terms of weight loss?

BECAUSE…

When you operate under the assumption that working hard at the gym is going to yield equally impressive results on the bathroom scale, you may be deeply disappointed with the outcome, which, in turn, may translate into disillusionment and very likely, a defeatist attitude.   “Nothing I try works” is a phrase I hear frequently from people who busted their butts at the gym for months, five days a week or more, only to see trivial changes in weight, sometimes, almost against all reason, on the plus side.  That all this work has improved their overall endurance is of little comfort when their pant/dress size has not changed for the better.

It’s not a matter of not having worked out hard enough, or long enough, or regularly enough.  It’s a matter of focusing on the wrong approach then feeling helpless when, after all the time and effort invested in it, the approach fails.

In a trial published in the Journal of American Medical Association in 2003, researchers monitored the weight fluctuations of 184 overweight women participating in various levels of physical activities over the course of 12 months (2).  The women were divided into four groups:

  • vigorous intensity / high duration exercise
  • moderate intensity / high duration exercise
  • moderate intensity / moderate duration exercise, and
  • vigorous intensity / moderate duration exercise.

All the participants benefited from varying levels of improvement in cardiovascular fitness by the end of the trial.   There was no significant difference in terms of weight loss between women at the high end of the intensity/duration exercise spectrum and those at the low end.  High intensity workouts lasting longer periods of time did not yield an advantage, in terms of weight loss, over moderate intensity and moderate duration regimens.

Similarly, the authors of a 2007 study looking at the effects of exercise on cardiovascular fitness divided 464 previously sedentary overweight and obese women participants into four groups: a no-exercise control group or one of three groups in which they expended 4, 8 or 12 calories per kilogram of weight, per week, for a period of six months by engaging in various intensities and durations of physical activity (5). Upon completion of the study, the authors found graded dose response changes in heart fitness across all levels of exercise, but no significant changes in weight.  Exercise alone, regardless of intensity or duration, did not amount to a hill of beans in terms of weight loss, even when routines were maintained for as long as six months.

Several factors account for these somewhat counterintuitive outcomes including increased hunger (and, thus, food consumption) as a result of vigorous exercise, a tendency for people to relax their calorie counting on the days they work out (or they think they can indulge today because they are going to work out tomorrow), the notion that they deserve a reward (read: chocolate lava cake) for all the hard work they’ve completed, and a host of other physiological and psychological factors.  These studies are mere drops in a virtual ocean of evidence that weight loss occurs in the wake of dietary changes, rather than as a result of vigorous exercise routines (6).  “Ah, but muscle weighs more than fat!” you might say, “so, no change in weight doesn’t necessarily mean no change in body size!”  True, but the overwhelming evidence suggests the lack of improvement is not specific to weight, but to overall measurements as well, whenever exercise routines are the only intervention. If study participants ended the trials several dress sizes smaller but weighing the same, there would be no point to having this discussion.

That being said, regular physical activity not only helps keep the weight off, but helps protect against a great number of diseases of affluence (cardiovascular disease, diabetes).  As such, it is an important part of any healthy lifestyle (7,8).

If you are trying to lose weight, it is important to focus on making permanent changes  to your dietary habits.  Popular fad diets don’t work in the long run and exercise alone is not going to help you reach your goals.  There is a sense of helplessness that accompanies the generally disappointing outcomes of making uninformed weight loss regimen choices.  You  may end up feeling as though nothing you try works, therefore, there’s no sense in trying.

A healthy diet that focuses on plant based foods goes a long way toward normalizing caloric intake, body weight and metabolic markers with or without the help of an exercise regimen (9,10).  Talk to a dietitian and/or qualified nutrition counsellor and get the help you need to make permanent lifestyle changes.  Some gyms have dietitians on staff whose services are included in your gym membership.  Work on your dietary habits/choices, and the rest will follow.  It is easier and healthier to watch your caloric intake than to fight an uphill battle while trying to  compensate for added calories by working out.

REFERENCES

  1. Centers for Disease Control and Prevention, Division of physical activity and obesity.  Why is physical activity important? 2012. Available at:  http://www.cdc.gov/healthyweight/physical_activity/  Accessed June 2, 2012.
  2. Jakicic JM, Marcus BH, Gallagher KI, Napolitano M, Lang W.  Effect of exercise duration and intensity on weight loss in overweight, sedentary women – a randomized trial.  JAMA 2003; 290(10): 1323-1330.
  3. Church TS, et al. Effects of aerobic and resistance training on hemoglobin A1c levels in patients with type 2 diabetes.  JAMA 2010; 304(20): 2253-2262.
  4. Scarmeas N, et al. Physical activity, diet, and risk of Alzheimer’s disease.  JAMA 2009; 302(6): 627-637.
  5. Church TS, Earnest CP, Skinner JS, Blair SN. Effects of different doses of physical activity on cardiorespiratory fitness among sedentary overweight or obese postmenopausal women with elevated blood pressure. JAMA 2007; 297(19):2081-2091.
  6. Rock CL, Flatt SW, Sherwood NE, Karanja N, Pakis B, Thomson CA.  Effect of a free prepared meal and incentivized weight loss program on weight loss and weight loss maintenance in obese and overweight women.  JAMA 2010; 304(16): 1803-1811.
  7. Hankinson AL, et al.  Maintaining a high physical activity level over 20 years and weight gain. JAMA 2010; 304(23): 2603-2610.
  8. Lee I, Djousse L, Sesso HD, Wang L, Buring JE.  Physical activity and weight gain prevention.  JAMA 2010; 303(12): 1173-1179.
  9. Newby PK, Tucker KL, Wolk A. Risk of overweight and obesity among semivegetarian, lactovegetarian, and vegan women. AJCN, 2005; 81: 1267-74.
  10. Vergnaud A, et al.  Meat consumption and prospective weight change in participants of the EPIC-PANACEA study.  AJCN 2010; 92: 398-407.

To spit or not to spit…


Candida albicans is a fungus which, along with thousands of other species of fungi and bacteria, lives symbiotically within the human body (1).  Proper Th1 (a type of lymphocyte) response of the immune system keeps its numbers in check as it goes about its daily business rendering it virtually incapable of producing infection or disease in the healthy host (1).  In immune suppressed persons, such as HIV patients or persons taking immunosuppressant medications, invasive growth may occur.

Candidal infections usually take over warm and moist areas of the body such as underarms, oral and genital areas.  Itching and irritation accompanied by rashes, blisters or painful cracks in the corners of the mouth (in the case of oral thrush), as well as discharge that resembles cottage cheese (in the case of vaginal infection) are the most common signs (2).  In rare cases, usually as a result of significantly depressed immune system function, the infection may spread to other areas of the body, and can affect the organs and blood (2). In such cases, symptoms are more severe, usually painful, with or without fever, and, if the infection is in the blood and spreads to the brain it can cause significant disruptions in mental function. Infections of this magnitude are usually life threatening (2).

Candidiasis affecting the skin, oral and/or genital cavities is treated with over the counter or prescription medications for a few days or a couple of weeks, whereas, infections affecting organs and the blood require hospitalization and intravenous medications as they can be fatal.

Infections affecting organs and the blood (aka “systemic infections”) occur primarily in hospital settings among patients undergoing immune system suppression (usually in the wake of transplant surgery or auto-immune disease/disorder treatment) (3).  The infection tends to recur several times during the first six months following surgery or immune system suppression treatment (4).  Its signs and symptoms are generally severe and require aggressive interventions.   Even so, death occurs in more than 1 out of 2 infected patients (3).  The good news is that infection rates hover around 2.9 per 100,000 people in Canada and anywhere between 6 and 10 per 100,000 people in the USA (depending on geographical region studied), making systemic candidiasis infections relatively rare (3).

ALTERNATIVE MEDICINE TAKE ON THIS

A surprising number of websites and their authors (who often also publish books on the subject or sell their own brands of remedies) may tell you that C. albicans is the leading cause of afflictions too many to list here, ranging from general fatigue and brain fog to asthma and obesity.  It takes over the body, organs, and blood, they claim, but keeps its population in check somehow, thus, remaining undetected by conventional methods, because, they say, physicians do not, or pretend to not, have the necessary technology.  However, they tell us that if we spit in a glass of water and watch what the saliva does over the course of 20 minutes, we can detect the infection ourselves. Of course, everyone’s saliva is going to do something similar (or exactly the same) to what is described in this so-called “test”, rendering it less than useless.

Whatever your symptoms, C. albicans is generally considered to be the main culprit and changing your diet (which almost always includes taking whatever supplement the website author is peddling) is the remedy of choice.  Science based medicine is often seen as having an agenda that keeps it from diagnosing and treating the infection.  Assuming the diagnosis and treatment would involve trading money for services / tests / medications rendered, this agenda must involve something far more valuable than mere dollars.  Whatever it is, its value exceeds the potential windfall that treating nearly 90% of the population (the number of people afflicted by C. albicans systemic infection, according to the “treatment” promoting websites – a far cry from the less than 0.0003% actually documented by the Canadian Journal of Infectious Diseases) would provide (3).

REALITY CHECK

C. albicans, in the absence of a normal immune system response, will do what any pathogen will do:  it will spread relatively quickly until something stops it.  That something is usually medical intervention that restores immune system function and/or attacks the fungus itself.  When no intervention takes place, infection spreads unchecked and death soon occurs.  This process does not take years- or decades-worth of suffering from nebulous afflictions.  An out of control infection acts relatively quickly, its signs and symptoms don’t beat around the bush, and even with the best of care and prompt intervention, odds of survival are not good.

REFERENCES

  1. Kosonen J, Rantala A, Little CH, Lintu P, Harjamaki PR, Georgiou GM, Cone RE, Savolainen J.  Increased levels of Candida albicans Mannan-specific T-cell-derived antigen binding molecules in patients with invasive candidiasis. Clinical and Vaccine Immunology, 2006;13(4):467-474.
  2. Molero G, Diez-Orejas R, Navarro-Garcia F, Monteoliva L, Pla J, Gil C, Sanchez-Perez M, Nombela C.  Candida albicans: genetics, dimorphism and pathoginicity. Internatl Microbiol,  1998;1:95-106.
  3. Bow EJ, Evans G, Fuller J, et al.  Canadian clinical practice guidelines for invasive candidiasis in adults. Can J Infect Dis Med Microbiol, 2010;21(4):e122-e150.
  4. Danovich GM, Handbook of Kidney Transplantation, Philadelphia, PA: Lippincott Williams & Wilkins; 2010:269.

Protein powders and shakes


A few decades ago, protein powders used to lurk in gyms and so-called “health” food stores. They were stacked neatly on shelves amidst colourful ads that lured would-be buyers with images of famous bodybuilders and athletes whose physiques few of them would ever match. In those days, their primary targets were body builders. Claims varied, but most brands promised increased muscle gain that, according to the ads, run of the mill, food derived protein could not possibly provide.

Today, protein powders have escaped the confines of gyms and health food stores and have become ubiquitous on food market shelves, in pharmacies, and virtually anyplace else food, supplements, or pharmaceuticals are sold. Their user base has changed dramatically to include athletes (professional sports people who are not bodybuilders), recreational athletes (sport hobbyists and/or fitness enthusiasts), and lifestyle users (consumers who think protein powders are healthy snacks and/or will help them lose weight)(1). Vegetarian and vegan consumers of protein powders tend to fall in the last two categories and are likely to believe the powders, or other similar supplements, are necessary to meet their daily protein needs. Some users claim they “feel better” and have more energy when they consume protein powders, while others simply believe that without their daily dosage, their muscles would vanish into thin air.

ENERGY

“The extra protein gives me energy!” is a claim I hear surprisingly often. It is surprising because protein is a lousy source of energy. It is a last resort the body will tap when it runs out of its preferred fuel (particularly during exercise): glycogen (aka stored carbohydrate)(2). You may have heard of athletes engaging in something called “carb-loading” before events. This consists of consuming a higher ratio of carbohydrates to help the body handle the energy requirements of extended activity, particularly if the event involves increasing pace and effort to beat the competition (3). The more intense the exercise, the more carbohydrate the body burns. Consuming carbs before and during exercise helps athletes keep up the pace. In fact, a high carbohydrate diet increases endurance time three-fold when compared to a high protein diet (3). Once glycogen runs out, so does your energy and ability to keep going. Similarly, failing to replenish your glycogen stores after exercise, will impair your ability to recover and achieve your training goals.

During periods of extended low intensity exercise, such as walking, fat becomes an important source of energy, more so if you engage in regular exercise. The more you train, the more your body uses fat for energy when you are resting or performing less strenuous activities. As you pick up the pace, your body switches back to using glycogen.

Image source:  McArdle et al. – Sports and Exercise Nutrition, 3rd Ed., Chapter 5, Macronutrient Metabolism in Exercise and Training, page 157 (3).

In a nutshell, if you’re looking for extra energy, put away the protein powder and have some healthy carbs instead.

MORE MUSCLE

Muscle growth occurs as the result of training, not from the overconsumption of protein. There is only so much protein the body will use before it stores the excess away. Protein powders are digested faster than food derived protein, making protein available for muscle repair in a more expedited manner. “Aha!” you might say, “so, they ARE good for something!” Well, not really. In the long run, the end result is about the same – except, perhaps, for your wallet.

Studies looking at the effects of supplementation and strength training combined show insignificant or no difference between placebo and control groups (2,4).  In their 2009 joint position paper on nutrition and athletic performance, the American Dietetic Association, Dietitians of Canada, and the American College of Sports Medicine concluded the following (5):

“Current evidence indicates that protein and amino acid supplements are no more or no less effective than food when energy is adequate for gaining lean body mass. Although widely used, protein powders and amino acid supplements are a potential source for illegal substances such as nandrolone, which may not be listed on the ingredient label.”

In other words, as long as you meet your body’s protein requirements, it doesn’t make much difference if you’re getting the protein fast, from a powder, or slower, from food. What matters most is timing (6). Consumption of protein and carbohydrate containing foods immediately after training is far more important if you want to see results. The sooner you eat, the better. Letting as little as two hours pass after a workout without eating will lead to a lot of disappointment on your part if you’re looking to build muscle mass (7).

PRE-, DURING and POST-EXERCISE NUTRITION

For best results in terms of performance and overall health (the latter is sometimes overlooked when people consider a plan of action in the short term), remember that supplements are not a replacement for healthy food choices.

Eat breakfast, consume the appropriate amount of calories for your body (don’t forget to eat healthy fats), stay hydrated and be sure to eat before and after exercise. If you like coffee or tea, you may be surprised to know that caffeine is an effective ergogenic aid, particularly in racing events, but also in short term, high intensity events, if consumed one hour before exercise (8,9). If you’ve given up coffee and tea because you think it will hinder your performance, dehydrate you, or interfere with electrolyte balance, you may want to reconsider your choice (8,9,10).

While studies on the effects of protein restriction on performance have yielded inconclusive results, the same is not true when it comes to carbohydrate restriction which has been shown to be detrimental (11,12). The importance of carbohydrate consumption after workouts can not be overemphasized. The aforementioned position paper on nutrition and athletic performance provides the following guidelines for performance athletes (5):

  • Carbohydrate recommendations for athletes range from 6-10 g/kg (2.7-4.5 g/lb) body weight per day depending on extent and duration of exertion (5).
  • Protein recommendations for endurance and strength trained athletes range from 1.2-1.7 g/kg (0.5-0.8 g/lb) body weight per day. The authors stress that food sources can easily meet requirements and supplementation is not necessary (5).
  • Fat intake should range from 20%-35% of total energy intake. Note that consuming less than this will not improve performance (5).
  • Before exercise, a meal or snack “should provide sufficient fluid to maintain hydration, be relatively low in fat and fiber to facilitate gastric emptying and minimize gastrointestinal distress, be relatively high in carbohydrate to maximize maintenance of blood glucose, be moderate in protein, be composed of familiar foods, and be well tolerated by the athlete.”(5)
  • During exercise, it is important to replace fluid losses and “provide carbohydrates (approximately 30-60 g per hour) for maintenance of blood glucose levels.”(5)
  • After exercise, “a carbohydrate intake of ~1.0-1.5 g/kg (0.5-0.7 g/lb) body weight during the first 30 minutes and again every 2 hours for 4 to 6 hours will be adequate to replace glycogen stores. Protein consumed after exercise will provide amino acids for building and repair of muscle tissue.”(5)

To put things in perspective, let’s consider the nutritional requirements of a 160 pound male professional soccer player:

Calories: approx. 4,000 per day
Protein: approx. 110 grams per day, or 11% of daily calories
Carbs: approx. 640 grams per day, or 64% of daily calories
Healthy Fats: approx. 111 grams per day, or 25% of daily calories

Notice that although 110 grams of protein per day represents quite a bit more than the amount of protein recommended for weekend athletes or sedentary persons, this amount does not represent a higher percentage of daily calories. In other words, it is not added (or supplemented) protein.

BOTTOM LINE

If the only way you are meeting your protein requirements is by supplementing with protein powders, there is something wrong with your diet. It should not be difficult to meet the recommended 10% to 15% of your daily calories in the form of protein. In fact, I would be very surprised if this is the case, given the abundance of food varieties available in North America. In the unlikely event you are not getting enough protein or the necessary ratios of essential amino acids, tweaking your diet will be better for your health (and for your wallet) in the long run than starting a protein supplementation habit.

REFERENCES

  1. Overview of the Sports Nutrition Market—Food, Beverages and Supplements, 2010; ISSN 1920-6593 Market Analysis Report, AAFC No. 10745E.
  2. Maughan RJ. Nutrition in Sport – Volume VII of the Encyclopedia of Sports Medicine. MA: Blackwell Science, Inc.; 2000.
  3. McArdle WD, Katch FI, Katch VL. Sports and Exercise Nutrition, 3rd Ed. MD: Lippincott Williams & Wilkins; 2009.
  4. Williams AG, van den Oord M, Sharma A, Jones DA. Is glucose/amino acid supplementation after exercise an aid to strength training? Br J Sports Med, 2001;35:109-113.
  5. Nutrition and athletic performance. Journal of the American Dietetic Association, 2009; 109(3):509-527.
  6. Poole C, Wilborn C, Taylor L, Kerksick C. The role of post-exercise nutrient administration on muscle protein synthesis and glycogen synthesis. Journal of Sports Science and Medicine, 2010;9:354-363.
  7. van Essen M, Gibala MJ. Failure of protein to improve time trial performance when added to a sports drink. Med Sci Sports Exerc. 2006;38:1476-1483.
  8. Cox GR, Desbrow B, Montgomery PG, Anderson ME, Bruce CR, Macrides TA, Martin DT, Moquin A, Roberts A, Hawley JA, Burke LM. Effect of different protocols of caffeine intake on metabolism and endurance performance. Journal of Applied Physiology, 2002:93:990-999.
  9. Paluska SA. Caffeine and exercise. Current Sports Medicine Reports, 2003;2:213-219.
  10. Bell DG, McLellan TM. Effect of repeated caffeine ingestion on repeated exhaustive exercise endurance.  Medicine & Science in Sports & Exercise, 2003; DOI: 10.1249/01.MSS.0000079071.92647.F2
  11. Knechtle B, Knechtle P, Mrazek C, Senn O, Rosemann T, Imoberdorf R, Ballmer P. No effect of short-term amino acid supplementation on variables related to skeletal muscle damage in 100 km ultra-runners – a randomized controlled trial. Journal of the International Society of Sports Nutrition, 2011;8:6.
  12. Ivy JL, Res PT, Sprague RC, Widzer MO. Effect of a carbohydrate-protein supple- ment on endurance performance during ex- ercise of varying intensity. Int J Sport Nutr Exerc Metab. 2003;13:382-395.