Nutritional Myths: Fact or Fiction?
Nutrition has not always had its front-row seat on the “Fun Science Topic” award due to its seemingly simple structure, after all, it’s just what someone eats. However, the recent pandemic has paved the way for nutrition to emerge as a potential competitor again. At the peak of its might, the Covid-19 virus disrupted essential healthcare services worldwide, even causing hospitals to close down due to an excess amount of patients. It is during those times that people around the world started to prioritise nutrition.
Capitalizing on that, there has been a surge of self-proclaimed social media influencers claiming to be human body experts and giving out nutritional advice to the general population. There is good advice, but there is certainly a lot of misinformation. Although I am no Ph.D. holder, I am an athlete that prioritises nutrition and am a big fan of reading research, hence, this article will aim to debunk some of those nutritional myths.
Carbohydrates make you fat
The first myth is definitely one that has been passed down from generation to generation, that carbohydrates make you fat and if you want to lose weight you have to avoid the carb demon at all causes. However, a basic understanding of the physiology behind weight gain will render this myth busted. The basis behind this myth is the carbohydrate-insulin model that states that because insulin is released when carbohydrates are ingested, that insulin acts on adipose cell receptors to enable glucose uptake, hence ingesting carbohydrates causes excess adiposity.
If that were the case, we would expect to see a rise in obesity rates in countries that feast on carbohydrates such as Asian countries, yet that is not the case in Japan with an obesity rate of 3.6% despite eating rice as their staple food. Studies have also shown that when people are assigned different diets, one low-carb, and one high-carb, with total calories equated, there was no additional weight loss in the low-carb group, in fact, the dietary fat restriction was shown to marginally edge out carbohydrate restriction in weight loss, due to the thermic effect of food.
What’s happening is that no particular macronutrient (carbohydrates, proteins & fats) is uniquely adipogenic and that causes weight gain is an excess in energy intake that surpasses an individual’s need. Imagine the body as a see-saw with the body’s energy needs on one end and an individual’s daily energy intake on the other. If the individual’s daily energy intake surpasses the body’s need, the see-saw tips and weight gain occurs, and vice versa.
Sugar causes diabetes
This second myth is a tricky one, while there is some truth to it, it is not as clear cut as we think. Fructose, a type of sugar has been shown in animal models to induce uric acid genesis. This led to those animals developing diabetes independent of fructose’s caloric value. However, a meta-analysis of controlled feeding trials has shown that fructose when fed in equal amounts as other carbohydrates did not seem to affect the uric acid level in humans.
There is still debate in this realm, but authors of the animal model study themselves have said that even if fructose did increase uric acid genesis independent of its caloric value, it is likely not to be clinically relevant. While it is true that sugar consumption (as a whole) is closely associated with the risk of developing type 2 diabetes (T2D), correlation does not equal causation. Although there aren’t any direct trials investigating high sugar vs low sugar on diabetics, one trial did show that high carbohydrate diets did as well as high monounsaturated fat (good fats) diets at helping improve diabetic symptoms.
One hypothesis is that sugar does not possess any special effects on developing T2D, but it is the fact that sugar often comes accompanied by fats, such as in the form of ice cream, which is a large source of calories that then leads to weight gain. This weight gain then causes the body’s cells to develop resistance to insulin, leading to T2D. In short, it could be that it is not sugar that causes diabetes, but the hypercaloric nature of foods associated with sugar causes weight gain past a personal fat threshold which leads to insulin resistance and subsequently T2D.
Fad diets
The emergence of social media has made it all the easier to promote something, and some people are misusing that power. Over the years, many different kinds of diets have emerged on the market, the ketogenic diet, the carnivore diet, the Weight Watchers diet, etc. Although many people do see health improvements with these kinds of diets, most of those health improvements can be attributed to weight loss if said individual is obese. Besides, there is no one size fits all diet in the world since everyone is born different and has different preferences. Where one person achieves success by limiting carbohydrates, another might feel too restricted and binge over the weekends.
Not only that, a lot of these diets have one thing in common, they either demonize a particular nutrient, such as the ketogenic diet demonizing carbohydrates or they demonize a whole food group, such as the carnivore diet demonizing plant products. Although these may help improve short-term adherence to the diet due to the elimination of trigger foods, they might pose the risk of nutrient insufficiency. For example, it would be much harder to acquire the necessary fiber on a carnivore diet. Therefore, the general guideline is to follow a diet that you can best adhere to which includes all the food groups, prioritising whole foods over ultra-processed ones.
Gluten-free is best for you
The creation of gluten substitutes such as xantham gum, guar gum, etc in baking has brought on a new wave of products, gluten-free products. Although these products are aimed at people with celiac disease, whose intestinal cells launch an autoimmune response towards gluten that causes discomfort and pain, many still advocate for the use of gluten-free products despite not having celiac disease. Despite what any would say, gluten is not bad for the human body and there is no need to avoid it if you do not have celiac disease or gluten intolerance. In fact, the avoidance of gluten may result in a reduced intake of whole grains which can cause nutrient deficiency and adverse health effects. Lastly, gluten-free is expensive.
Eating after a certain time is bad for you
This is a staple myth among the older generations, but have resurfaced recently, the myth that eating anything after X time is bad for you. The problem with this boat of thinking is that where do you actually draw the line, is an apple at 6:59 p.m. the best food you can eat in the world, which then turns into a fat accumulating junk at 7:01 p.m.? It doesn’t really make any sense from a common sense standpoint and randomized controlled trials have shown that the timing of a meal is much less important than the quality of the meal and the total energy balance throughout the day.
In fact, a pre-bed casein protein shake has been used to increase overnight muscle anabolism to counteract sarcopenia and preserve muscle mass in the older individual. Similarly, intermittent fasting or time-restricted eating where individuals fast for a certain period and only eat in a certain period is also not inherently better than normal meal frequency. Sure, it might help some people restrict calorie intake due to the smaller window of eating, but others may over-eat and overcompensate during the window of eating causing weight gain.
Trials, where participants are put on isocaloric diets but in an intermittent fasting protocol or a normal protocol, showed no significant differences between the two groups. Emerging evidence does suggest that there may be a very small effect of concentrating more calories early in the morning due to the circadian rhythm, but the trials have small sample sizes and do not account for individual variances in circadian cycles; therefore, it is still too early to say that meal timing is a huge factor in health optimization.
Conclusion
With the emergence of the internet, knowledge can be accessed at the tip of our fingers. However, we still need to make sure the information we are getting has sources that back it up. Perhaps blindly following advice on social media has served you well, but who knows when your luck will run out? Hence, my final advice would be to always check and think critically about the information you see online, and if you don’t have the time to do so, follow trustable experts that are able to simplify the general scientific consensus for you.
By: Jared Ong
