Why fats aren't as bad as you may think
Fatty foods have long been the target of scorn from nutritionists and health nuts alike.
But according to Dr. Mark Hyman, author of New York Times bestseller Eat Fat, Get Thin, many of our preconceptions about fats are based on decades of misguided research.
"We were told that fat as the villain, and if you eat fat you get fat, and if you eat fat you get heart disease — and it's really not true," he told host Gloria Macarenko on CBC's BC Almanac.
Hyman says that these beliefs have been thoroughly disproved. He points to a scientific review of dozens of observational health studies that found there is no clear link between heart disease and saturated fats. Foods high in saturated fats include coconut oil, butter, nuts, poultry and red meat.
The effect of saturated fat on overall health still remains a contentious topic among nutritional scientists. While a 2016 study from the American Journal of Clinical Nutrition found that consumption of lowly-processed saturated fats in conjunction with fresh vegetables and rices decreased fat storage and risk of heart disease, many health authorities continue to recommend diets low in saturated fats.
Fat doesn't necessarily make you fat
Hyman says the key to losing weight isn't to cut out fats entirely — it means limiting the amount of carbohydrates you digest, in addition to eating lowly-processed fats.
He says the association between weight gain and fats has been misconstrued over time.
"What we now know is that not all calories affect the body in the same way, and that carbs, starch calories and sugar calories raise the hormone insulin, which is the fat storage hormone," he said. "It makes you hungry, it makes you store fat, it actually causes your metabolism to slow down, and it locks the fat in the fat cells."
When you eat fat, you don't produce any insulin, and your body won't store the same amount of fat, says Hyman.
Scientists refer to this connection between carbs and obesity as the carbohydrate-insulin hypothesis. It's the foundation behind many weight-loss plans, including the Atkins diet, and the increasingly popular ketogenic diet.
Healthy fats
The government of B.C. recommends including a small amount (about 30-45 mL or 2-3 tablespoons) of plant-based or unsaturated fats each day. These include:
- Avocado.
- Canola oil.
- Corn Oil.
- Fatty Fish (salmon, tuna, mackerel, trout, sardines).
- Flaxseed.
- Nuts (almonds, hazelnuts, peanuts, pecans, walnuts).
- Olive oil.
- Olives.
- Peanut butter.
- Safflower oil.
- Peanut oil.
- Sesame oil.
- Soybean oil.
- Pumpkin seeds and oil; sunflower seeds and oil.
With files from CBC's B.C. Almanac
To listen to the full interview, click on the audio labelled: Why fats aren't as evil as they've been made out to be