Myth : Eating fat makes you fat

The low-fat diet craze may have had it's heyday in the late 1990s, but the myth that fat is bad for you or leads to weight gain persisted well into the 2000s and beyond.

But the past few years have shown that "lite" versions of popular products are actually worse for your health, increasing the risk of heart disease and other ailments previously linked to high-fat foods.  

Now the trend has swung in the opposite direction, with high-fat diets like keto more popular than ever and carbohydrates, particularly sugar, now vilified as causes of obesity and illness.

Plenty of high-fat foods are perfectly healthy. However, fat is still more calorie-dense than either carbs or protein, so it can have mixed effects on weight loss.