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Health

The Red Meat Controversy

Diet studies are difficult to do properly. It is simply too difficult to control the many factors that influence our health while comparing different diets. Most diet studies, therefore, are poor quality and based on weak evidence. Even the ideal type of study, known as a randomized controlled trial (RCT), isn’t perfect as people can’t live in a bubble for the entire study time.

And animal studies, where it is easier to control all factors, don’t necessarily apply to humans. A famous one, where rabbits were fed high amounts of foods containing cholesterol and subsequently developed heart disease, didn’t take into account that rabbits never naturally eat cholesterol-containing foods and probably can’t digest them – they live on salad! Human studies have found that it’s not possible to lower blood cholesterol significantly by reducing cholesterol intake because the liver makes cholesterol when it is lacking in the diet. However, we continue to see “low cholesterol” foods promoted as being good for our heart health. Here is a referenced article about this. Essentially, all conclusions from dietary studies need to be “taken with a grain of salt”.

But a new study “McMaster university – New guidelines: No need to reduce red or processed meat consumption for good health” bases its conclusion on the lack of good evidence for us to change. This research was conducted by 14 researchers in seven different countries. They state: “Evidence of harm from moderate consumption of red or processed meat is poor and health benefits, if any, would be small.” The study also considered the desirability and enjoyment of a juicy steak and the “hardship” vs. benefits of a rather drastic change in diet. (Note that it excludes any ethical or to environmental concerns, focusing only on evidence that people need to change their meat consumption to be healthier.)

More than anything else, to me this study points out the trend to make dramatic announcements for radical diet changes based on poor quality information. This study doesn’t suggest red or processed meats are healthy or that people should eat more of them, but researchers don’t discount the possibility that there are millions of people who eat a lot of meat and who are in good health.

That being said, another article published in the journal, The Lancet, suggests that the “healthiness” of cutting out the red meat depends on what it is replaced with. Reducing meat consumption, according to this study, is only likely to benefit health if the meat is replaced with plant-based foods. Replacing it with “white foods” (white rice, white bread, potatoes and sugar) doesn’t result in improvement to health, according to this study.

An article in Healthline seems to sum it all up quite well. It suggests that red meat doesn’t affect health significantly but that processed meats, depending on the additives used and cooking processes, might change the health effects of eating meat. But, like all diet studies, the evidence isn’t strong. Here is the link if you’d like to read it.

Of course, these studies address only the effects of meat on human health. The environmental impact of raising animals and the ethical issue of using animals as a food source are issues that also should be considered in a complete discussion.

What I found so interesting in these studies, was that the evidence that red and processed meats harm our health is very weak and the benefits of such a dramatic diet change are small. The researchers found there is simply not strong enough evidence to insist that all humans need to make this radical diet change.

For myself, I enjoy eating meat but find these days that a small amount is enough. The photo above was part of a 7-course meal in a fancy restaurant, and was a small but very delicious and satisfying serving. We also enjoy seafood of all kinds in our house and the occasional vegetarian meal too – especially homemade pasta sauce with lots of veggies added. Mostly we are trying to increase our consumption of fruits and vegetables these days to improve our diet. Sweets and desserts have become the exception (not the rule!), too, to lower our sugar intake.

I still like Michael Pollan’s Food Rules the best: Eat real food (not processed), mostly plants, and not too much. Everything in moderation makes sense unless you have good reason to change.

So, have you many any changes to your diet recently? Did it help you to feel better or improve a chronic problem? I’d love to hear about it…

References:

This diet is better for the planet, but is it better for you too? – NPR

Health and Nutritional Aspects of Sustainable Diet Strategies – The Lancet

Why Dietary Cholesterol Does Not Matter for Most People – Healthline

Categories
Health Public Health

Fat vs sugar – time to rethink!

Sugar is the problem — not fat. Years of advice to choose low-fat and fat-free foods does not appear to have been based on sound research…

New Canadian research found no significant association between eating more than the recommended amount of fat (30% of total calories) and developing heart disease or having a stroke. In fact, they found that those who got 35% of their energy from fat had a lower overall risk of dying than those who ate less than the recommended 30%!

In addition, they found that the low-fat diets recommended to us for many years have resulted in many people overeating carbohydrates, resulting in a higher risk of dying when their carbohydrate intake exceeded 60% of their total calories. Replacement of dietary fat with sugary carbohydrate is also being suggested as a cause of the current increased rates of obesity.

Scientists lead by nutritional epidemiology expert, Mahshid Dehghan at McMaster University in Hamiltion, Ontario, studied diets of 135,000 people in 18 countries for an average of 7 years. She observed “When you recommend lowering fat, by default, people increase their carbohydrate consumption, and increasing consumption of carbohydrates results in higher risk of mortality.”

Study in Japan

This Canadian finding agrees with another article I recently read describing how the stroke rate in Japan dramatically fell almost 6-fold from 1,334 to 226 per 100,000 between 1958 and 1999, after the government encouraged the population to increase their intake of fat. Cholesterol levels rose from an average of 3.9mm/l to 4.9mmol/l due to dietary fat rising from 5% to 20% of total calories. Heart disease rates, interestingly, also decreased although not as dramatically. This is a stark contrast to our current recommendations to lower cholesterol in the blood as much as possible to reduce the risk of heart disease…but more about that in a future blog!

Population studies

Studies of diets from diverse healthy populations suggest that there is not one single “best” diet. The high-fat diets of the Innuit of the north, the Maasai tribes of Africa and the French in France seem as healthy for their populations as the low-fat Mediterranean diet of Italy.

This has lead some to speculate that it is not so much what we eat (as long as the diet is a traditional balanced one) but how much we eat and ­how we eat. Avoiding overeating and enjoying food in a relaxed environment with family or friends (rather than eating on the run or in your car!) seem to be positive factors for overall health too!

Canada Food Guide 2018

Even our Canada Food Guide is being revised…and I hear the meat and dairy industries are not happy with the plans. Although the new finalized guide will only be released in two stages over 2018 -19, Health Canada says less emphasis will be placed on individual nutrients and more will be placed on:

  • avoiding processed foods (that commonly have added sugar, trans fats, salt and other ingredients),

  • reducing consumption of sugary drinks, and

  • limiting portion sizes.

This seems to agree with other experts like University of Toronto’s nutritional scientist, Richard Bazinet who advises “Moderation is the solution. Don’t eat too much of any single thing” and Michael Pollan’s Food Rules: “Eat food (real food, not processed). Mostly plants. And not too much.” Check out my previous blog on his Food Rules here.

It seems difficult to understand why low-fat diets have been recommended for so long – some suggest that influence from the sugar and grain industries may have been a factor. Currently, news outlets have reported meat and dairy industry lobbyists are “up in arms” against the suggestion that the new Canada Food Guide may decrease emphasis on consumption of these food groups.

However, the purpose of any food guide or advice is to improve the health of a population, not to support food industries. Health Canada has stated that it will not be consulting with food producers, although they are permitted to engage in open public consultations.

Trans fats

When it comes to fats, however, there seems no question that trans fats should be avoided. Trans fats, also known as hydrogenated oils, are stable artificially created fats that have been used to extend the shelf-life of processed foods…good for food, but not good for our health! Trans fat content appears on food labels so you can avoid buying foods containing these fats, and some governments are moving to ban these completely from food!

Trans fats often occur in foods that also contain saturated fats and may be responsible for the bad reputation assigned to saturated fat. Wikipedia has an interesting summary of studies comparing the effect of saturated fat (SFA) with unsaturated fat (PUFA). At the very least, one could say there is conflicting evidence when it comes to the dangers of saturated fat, with newer studies being less likely to find that fat in the diet has any effect on heart disease. It will be interesting to see what the new Food Guide recommends as an ideal amount of fat in the diet, considering the results of new studies!

Have you been cutting fat out of your diet? Leave a comment below!

References: