Back in the 1950s, a small study was done by an influential scientist who made recommendations about nutrition, and these were adopted by the American Heart Association and other groups in regard to heart health, diet and weight loss. In recent years, better studies have been done and the medical field is slowly getting on board with giving updated and more accurate advice with this new information. I want to apologize and take responsibility for giving wrong advice to my patients when I first started practicing medicine back in the early 1990s.
Allow me to debunk some of the big myths:
Myth 1: Take in fewer calories than you expend and you will lose weight
Fact: The low calorie approach to weight loss doesn’t work long term as evidenced by our obesity epidemic. Research has shown that when you cut calories, your body fights back by making you hungry and by slowing down metabolism. Basically the body goes into “survival” mode, burning fewer calories and making you ravenous to avoid starvation
Myth 2: All calories are created equal i.e. eating 200 calories from sweets or starches (carbs) is the same as eating 200 calories from protein or fat
Fact: your body’s response to carbohydrate calories is dramatically different from your body’s response to protein and fat calories. Highly processed carbs (sweets and starches) raise your blood sugar very quickly. This triggers your pancreas to release a large amount of insulin, which in turn causes your body to store those calories in fat cells (and essentially lock it in). That then causes blood sugar to drop, which triggers hunger and slows metabolism. The vicious cycle continues (carb craving leading to binge eating). Eating more protein and fat with fewer carbs helps reprogram your fat cells to release excess calories, giving you energy and turning off hunger signals
Myth 3: Fat is bad, I need to eat low fat to lose weight and be healthy
Fact: Healthy fats (found in things like olive oil, nuts, and eggs) are very helpful when you are trying to lose weight. They trigger satiety (feeling full) centers and shut off hunger (craving) centers in your brain. They also may decrease inflammation in your body which is good for joints and heart health
Myth 4: Eggs, especially the yolks, should be avoided because they are high in cholesterol and increase risk of heart disease
Fact: For most people, eggs do NOT increase cholesterol nor contribute to heart disease. They are actually one of the most nutritious foods to eat because of their high protein content. They also can contribute to increase in good cholesterol (HDL)
Myth 5: Stay away from saturated fats found in meat and dairy products because they increase cholesterol and risk of stroke and heart attack
Fact: Several recent studies have shown that saturated fat consumption does not increase the risk of death from heart disease or stroke. For most people, eating reasonable amounts of saturated fat is safe and healthy. The quality of meat and dairy may make a difference with grass-fed beef/dairy being preferable
Myth 6: The only people who should go gluten-free are patients with celiac disease, about 1% of the population
Fact: It is often claimed that no one benefits from a gluten-free diet except patients with celiac disease (the most severe form of gluten intolerance, affecting under 1% of people). But another condition called gluten sensitivity is much more common and may affect about 6-8% of people. Studies have also shown that gluten-free diets can reduce symptoms of irritable bowel syndrome, schizophrenia, autism and epilepsy. However, gluten sensitive people should eat foods that are naturally gluten free (like veggies, fruits, and animal products), not gluten-free “products.” Gluten-free junk food is still junk food.
Myth 7: Losing weight is all about willpower
Fact: The human body is a highly complex biological system with many hormones and brain centers that regulate when, what, and how much we eat. Genetics, hormones, and various external factors including stress levels have a huge impact on body weight. Junk food is very addictive, making people quite literally lose control over their consumption. Although it is still the individual’s responsibility to do something about their weight problem, blaming obesity on some sort of moral failure is unhelpful and inaccurate.
Myth 8: As long as I eat healthy foods, portions don’t matter
Fact: Foods such as avocados, nuts and olive oil deliver heart-healthy fats but must be used in moderation. Red wine and dark chocolate are full of antioxidants which are healthy, but if you indulge in a lot, you’re likely to not be able to lose weight. Portion sizes of any food matter. Additionally, high carb fruits like bananas, pineapple, and melon can cause a spike in blood sugar which starts off the vicious cycle described in Myth #2 above.
References: JAMA article June 27, 2012; NEJM article October 4, 2012