Despite continuing advances in science – many myths persist about our diet, why we get fat, how we get ill and how best to control our diet and lose weight. Some are over simplified views while others are genuinely misleading and persist despite a lack of supporting evidence – or evidence to the contrary.
Here are seven of the big ones – some of these may come as a surprise.
1. Weight Loss is Simply Calories in = Calories out
While this logic at first makes perfect sense – it is in fact overly simplistic and misleading.
We now understand that different food affects different people in different ways – as each of our bodies and metabolisms work differently. Some of us can indulge in ice cream and doughnuts and never seem to get fat – while many of us put on weight all too quickly.
Far more important than our caloric intake is the type of food we eat and the source of that food. For example our bodies break down and absorb fewer calories from a green unripened banana than from a ripe yellow banana.
As we learn more about our gut microbiome we keep discovering how it affects our energy absorption, our metabolism and our health in different ways. There is much evidence that obesity is a complicated disease associated with an in balance of the bacteria in our gut that affects our metabolism and how we extract and store energy from food in our diet.
2. Breakfast is The Most Important Meal of the Day
This is an often quoted statement repeated by many public health authorities who recommend breakfast consumption to reduce obesity, however this is in fact misleading
Two randomized, controlled trials that studied the outcome of eating versus skipping breakfast showed no effect on weight in the total sample. However, the findings in one study suggested that the effect on weight loss of being assigned to eat or skip breakfast was dependent on baseline breakfast habits.
3. Exercise Is Important for Weight Loss
Don’t get me wrong – exercise is important – just not for the reasons you may think. When it comes to weight loss exercise just isn’t as helpful as we all believe – as physical activity only burns up 10-30% of the energy we get from food.
What’s more physical activity can increase the amount you eat and what you eat. While exercise is fundamentally important for our health in so many different ways – doing a few extra laps or minutes on the tread mill isn’t going to help you slim down its own. What matters far more is what you eat.
However while exercise led to only modest weight loss in various studies, participants who exercised more (even without changing their diets) saw a range of health benefits, including reduced blood pressure and triglycerides, a reduced risk of Type 2 diabetes, stroke, and heart attack.
We also know that exercise changes our microbiome with positive health benefits. A number of other studies have also shown that people who exercise are at a lower risk of developing cognitive impairment from Alzheimer’s and dementia. They also score higher on cognitive ability tests — among many, many other benefits.
4. Eating Fat Makes You Fat
Despite this myth being debunked it is sadly still prevalent today- and still astonishingly to this day many health authorities advocate the low fat diet. While we don’t suggest all fat is good or that a high animal fat diet is good – fat isnt the villain it has been portrayed as.
In one of the largest and most expensive dietary trials ever conducted –the Women’s Health Initiative Dietary Modification Trial, costing over $600M failed to show any benefit from going on a low-fat diet.
In this study, 49,000 women were randomly assigned to either a low-fat diet or to continue their normal diet.
The low fat dieters reduced their fat consumption from 35% to 29% and were followed for eight years, after which the low fat group were found to be no better off than the control group, either in terms of weight or rates of heart disease, cancer or stroke.
The Origins of The Low Fat Diet Myth
The vilification of fat dates back to the early days of dieting and calorie counting a century ago. However it wasnt until the US Department of Agriculture’s released a set of dietary guidelines in 1980 identifying fat and saturated fat as the cause of high blood cholesterol and heart disease that fat became public enemy no. 1. (The guidelines were based on flawed scientific evidence).
This anti-fat stance was then adopted by other health boards such as the American Heart Association (AHA) and gained further momentum when it was seized upon by the food industry to create all sorts of low fat ‘health foods’ laced with carbs, sugars and sweeteners.
5. Diet soft drinks are better than sugar drinks
The common belief promoted by the food industry is that diet sodas and artificial sweeteners allow you to get all the enjoyment of sugar without any of the calories.
However in a recent report, published in the Canadian Medical Association Journal, researchers analyzed 37 studies into artificial sweeteners to see the effects on weight management and health. The studies – which tracked over 400,000 people for about 10 years, including 7 randomized controlled trials, suggested that people who regularly drank soft drinks or foods containing artificial-sweeteners had a higher risk of weight gain and obesity, and also diabetes and heart disease.
One possible cause was highlighted in a study at the Weizmann Institute of Science, Israel(2014) where artifical sweeteners were found to alter our gut microbiome increasing the composition of several strains of bacteria associated with obesity, diabetes, and metabolic disease. These changes to the microbiome were found to induce inflammation in the liver which is known to induce glucose intolerance – any early from of diabetes.
6. Skipping Meals is Bad For You
Many myths persist that skipping meals is bad and that this results in missing essential nutrients and that it causes the body to go into starvation mode, resulting in reduced muscle mass.
In fact intermittent fasting has been found to have remarkable benefits:
In various studies, fasting has resulted in measurable metabolic benefits for obese people and reducing the risk of diseases, while in animal studies, intermittent feeding and fasting reduces the incidence of diabetes and improves certain indicators of cardiovascular health.
In another study of 71 adults, at the University of Southern California, found that fasting for five days a month (consuming between 3138 and 4600 kilojoules on those days) reduced cardiovascular risk factors, inflammation levels, waistlines and total body fat, but not muscle mass.
7. It’s best to lose weight gradually to keep it off
There are a large number of articles around the web advising a gradual approach to weight loss in order to keep the weight off. However in clinical weight loss trials the opposite has been found to be true; and that both rapid and greater initial weight loss is associated with lower long term body weight.
In a study at the University of Melbourne in 2014, 200 overweight women were randomly allocated to either a rapid weight loss program – to lose 12.5% of their total body weight in 12 weeks – or gradual weight loss program where they had 36 weeks to lose the weight.
The found the dropout rate in the slow weight-loss group was as high as 50 percent whereas in the rapid weight loss group 85 percent of the participants successfully lost the weight. Furthermore in a follow up 2 years later the slow group were found to have put on the most weight
Although its recognised that some people lose weight more slowly than others, any recommendation to lose weight gradually can interfere with the ultimate success of weight-loss efforts.