Sunday, July 31, 2011

Health education with Dr T. Colin Campbell - Nutrition, Food and Supplements


As my hero Dr John McDougall has just spoken out on the supplement issue, here is my own assignment on ascorbic acid (Vitamin C) on that topic from Dr T Colin Campbell's Certificate in Plant Based Nutrition.
This research on the Vitamin C story was by far the most difficult assignment for me.  I gained valuable insight into my own regular dependence on supplementation in favour of healthier food choices.
Dietary supplements are often promoted as healthy alternatives to pharmaceutical drugs prescribed by doctors. Contrary to this perspective, Dr. Matt Lederman suggests that supplements may not be as innocuous as commonly thought:

"Our bodies were designed to get their nutrients from food in a system that has evolved over billions of years. Supplements are not food. We absorb vitamins and minerals from our food better than from a supplement. Modern chronic disease is not due to specific nutrient deficiencies. And supplements don't cure or prevent chronic disease.

"The data continue to show that supplements in general do not improve health (unless one has a proven deficiency) and often cause harm once well studied (vitamins A, E, and beta carotene all increase mortality). As far as I am concerned, supplements are medications at best and should be treated as such."
Choose a common supplement that you take yourself, think could be beneficial, or that you are interested in, and research it. Filter through the advertisements, advice, and promotions and seek out alternative views. Are there any concerns with taking this supplement? Think about the life cycle of this supplement from production to consumption, and imagine the impacts of making, selling, and consuming this product.

Consider looking at such issues as where this supplement comes from, how it is manufactured, what it is made of, how the quality of this supplement is regulated or measured, who is selling it, the relative costs and benefits of using it, and anything else that will help you to consider the costs to individual health or greater well-being involved with taking it.

In a brief overview, share with the class:
A. Your supplement of choice
B. The three to five most compelling reasons you discovered to avoid taking this supplement

In our follow-up discussion, explore any changes to your views on supplements, or what supplements you still consider beneficial and why.

Why C?

I must address vitamin C, our family's traditional supplement (and the only one apart from B12 that I use regularly). My parents believed that Linus Pauling's research is sound, and from a very young age, I have had pure ascorbic acid (vitamin C) dissolved in juice.

I normally take about a gram of ascorbic acid in water in the mornings. When I am sick, I increase the dose to many as many grams as I can manage. I have always believed the evidence shows that vitamin C supplementation has multiple benefits as an antioxidant, antibacterial, anti-inflammatory, and general immune system support. The basic argument is that humans need vitamin C, do not produce it, and do not get enough from their food for optimal health.

Over this course, I have come even more to the point of view that whole foods are health promoting. Dr Lederman's supplement lecture also showed compelling evidence about problems with individual supplementation. So I have been very interested to look more deeply into the available research on vitamin C.

There is almost too much research on vitamin C! (I even found a reference to using C in dogs...

Vitamin C as medicine
Dr Lederman says "supplements are medications at best, and should be treated as such." So I will mention but not discuss the overwhelming (and fascinating) area of IV supplementation of vitamin C in 20g megadoses successfully treating severe illness like cancer and septic shock.

Also, while controversial at the "popular medicine" level, there is reliable and repeated evidence showing that oral vitamin C megadose (several grams/day) treatment at least reduces the duration of minor illnesses such as flu or upper respiratory infection. I can personally vouch for Vitamin C's anti-inflammatory activity reducing uncomfortable symptoms of such infections.

Daily supplementation
Daily supplementation is recommended at about 1g/day for general immune support, antioxidant behaviour, etc. This is far above the RDA's level needed to prevent scurvy from severe vitamin C deficiency.

"The RDA continues to be based primarily on the prevention of deficiency disease, rather than the prevention of chronic disease and the promotion of optimum health." Oregon State University
Studies have shown that C not only aids recovery from illness, it also may help to prevent infection in high risk populations. C supplementation has also been associated with reduced coronary heart disease in women and a long list of other health benefits.

Concerns about vitamin C supplementation

There is a wealth of controversy about vitamin C in the medical world. One major factor is a disagreement about how C is absorbed in the body: the concept of tissue saturation as studied by the National Institute of Health implies that absorption is maximised at a low level of C intake. These studies have been highly criticised and not well defended.

Excess vitamin C has also been theorised to cause kidney stones. As a close family member has been diagnosed with kidney stones, I checked this out very carefully, but it is generally agreed that there is more evidence that vitamin C prevents kidney stones!

A last personal anecdote: I have always had thin enamel on my teeth. At times when I have used oral megadoses to fight an infection, I have damaged my teeth temporarily when I haven't been careful to neutralise the acid in my mouth after I take it.

What about whole foods?

This recent story on VegSource holds the key. If I ate fruits and leaves all day, like our close relatives the gorillas, I would get much more vitamin C from my food.

Roughly estimated, I could get 1000mg of vitamin C from whole raw food in a day from:
100g kale, 200g kiwifruit, 200g broccoli, 200g cauliflower, 50g parsley, 200g oranges, 100g strawberries and 100g yellow peppers. Clearly, this would be a diet much closer to those healthy gorillas!

The vitamin C would be arriving in small doses all during the day (generally agreed to be the best way for the body to use it). And my immune system would need less protection, since I would not be eating processed or high fat foods.

I would struggle to get megadoses of the multiple grams from whole foods only, but arguably I would rarely be sick enough to need them.

I find no compelling evidence of dangers of supplementing with vitamin C and instead, some great advantages to people eating a modern diet. We have two children in public education (germ zoos) and have chosen not to vaccinate, so I would not hurry to stop supplementation.

However, ascorbic acid supplements are not cheap, and vitamin C is readily available from fresh fruits and vegetables. My review of vitamin C research motivates me to add more, and a wider variety, of fresh fruits and vegetables to my and my family's diet and reduce the amount of the expensive supplement I use on a daily basis. This will be more palatable and easier on my teeth.

And if we ever eat like healthy gorillas, I know we can stop supplementing!

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