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Pretty boring compared to magic juice, but much better for you

Op-ed: Three popular nutrition diet trends to steer clear of — based on best evidence

April 17, 2017 — 

The following is an op-ed written by alumnus Dylan MacKay [PhD/14], an expert adviser with and a nutritional biochemist at The Richardson Centre for Functional Foods and Nutraceuticals in the Department of Human Nutritional Sciences at the University of Manitoba. He also works on TMPLR (The Manitoba Personalized Lifestyle Research Program, a U of M-led investigation into how diet, activity and sleep impact chronic disease risk). This article originally published in the Vancouver Sun on April 15, 2017. If you enjoy this, you may also like when he debunks some raisin studies


If you follow health tips in the media, you’d think the nutritional sciences are a mess: Is butter good for you or is it bad? Should I eat breakfast or skip it? Should I eat like a caveman? Or maybe should I eat more like a bird?

“Alternative facts” aren’t a new concept in the field of nutritional science. Too bad so many people fall for them. 

Fortunately, it’s still possible to use scientific evidence to separate the wheat (safe to eat, unless you have celiac disease) from the garbage. So, here are three popular nutrition diet trends to steer clear of — based on best evidence:

1. Skip the ‘detox’ or ‘cleanse.’


Do you have evidence of that?

Anyone selling a diet, juice or anything else to help you ‘detox’ or ‘cleanse’ is going beyond the bounds of good evidence.

The concept of ‘detoxes’ or ‘cleanses’ hinges on the idea that our bodies are being filled up with ‘toxins’ that are making us sick and need to be removed. But just ask “what toxins?” and you get crickets chirp.

Scientists have long understood that our bodies have developed sophisticated pathways that naturally detoxify and then excrete unwanted substances. Some of the substances that we need to get rid of are created by our normal bodily functions (bilirubin, urea), some we ingest on purpose (drugs, alcohol) and others come from our environment (pollutants, heavy metals).

The detoxication pathways depend on the substance, but typically include conversion to a less toxic form, or involve binding with proteins, making them easier to excrete in the urine or gastrointestinal tract. 

2. Skip the alkaline/pH diet.

One of the biggest proponents of pH diets is currently in jail for practising medicine without a licence — and these diets, which are often promoted to cancer patients, simply don’t work.

pH or alkaline diets promote eating foods that are “alkaline” and limiting acidic foods, with the idea that acidity can accumulate and is harmful to the body.

But our body’s pH range isn’t influenced by what we eat or we’d all be dead; our proteins would denature and critical enzymes in our body would stop.

Fortunately, our bodies can maintain a tightly controlled pH range (~7.35-7.45). This is a process referred to as acid-base homeostasis. Values outside of this range are caused by serious health problems, like diabetic acidosis or kidney disease, not by eating too much fruit.

People promoting pH or alkaline diets are full of something, not shame. They can be ignored because taking health advice from someone who would fail basic biochemistry is a bad idea.

3. Skip the intravenous vitamins and nutrients.

Intravenous (IV) nutritional therapies, which deliver vitamins, minerals and amino acids, are marketed for just about anything — hangovers, the immune system, athletic ability and cancer (nope).

Such IV therapies have been endorsed by celebrities and athletes and are happily sold by your nearest ‘alternative’ health-provider. The problem is, there is no evidence that they work, and they may actually be dangerous.

IVs have an inherent risk of infection, and may even cause potential toxicity as a result of bypassing the normal digestion process. 

There is a place in medicine for receiving nutrition by IV — it’s called total parenteral nutrition, but only if you are very ill or have a condition that prevents you from absorbing nutrients properly.

Scientists know that nutrients or foods should be eaten and not hooked directly to our veins — yes even coffee. Also, speaking of coffee, we should stick to drinking it with our mouths. 

So what’s good for us? What should we eat?

Evidence tells us that healthy eating involves vegetables, fruits, nuts, beans and not too much food. There are many things you can do to help your body stay healthy that don’t involve paying anyone. Start by not smoking, being physically active and getting enough sleep.

I know, pretty boring compared with magic juice.

One final suggestion for staying healthy: Don’t go to service-providers that sell detoxes, cleanses or IV nutritional therapies. Don’t visit their websites, don’t like or share their posts and don’t buy their books.

Friends don’t let friends get taken advantage of by “fake nutrition.”


Research at the University of Manitoba is partially supported by funding from the Government of Canada Research Support Fund.

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