13 diet 'truths' that are doing more harm than good

Eating healthy is hard work, so it's no surprise that many of us have tried a shortcut or two at some point, hoping for speedy results.

But some of these alleged nutritional quick-fixes aren't all that useful, and a handful of them can even be dangerous.

Here's a look at the most insidious food and nutrition myths, along with the science that debunks them.

SEE ALSO: Americans have been making a huge diet mistake for 100 years — here's what they should do instead

DON'T MISS: The first thing to cut out of your diet if you're trying to lose weight, according to a nutritionist

Myth: You should never 'cheat' on a diet.

Truth: It's perfectly fine to go off your healthy eating plan every once in a while, Nichola Whitehead, a registered dietitian and nutritionist with a practice in the UK, tells Business Insider.

"It’s alright to overeat occasionally," says Whitehead. "It’s overeating consistently day in and day out over the long term that causes weight gain."

If you've managed to switch from a diet heavy in red meat and processed carbohydrates to eating mostly vegetables, whole grains, and lean proteins, you've already done the majority of the work, Whitehead says. 

Myth: Counting calories is the best way to lose weight.

Truth: Although counting calories can be a useful tool in a bigger toolkit for weight loss, it is not a perfect solution for healthy eating, especially when it's used in isolation.

That's because restricting calories doesn't take into account all the aspects of a food that are required to fuel your body, from protein and carbohydrates to vitamins and minerals. Whitehead summarizes the problem this way: "While calories are important when it comes to losing, maintaining, or gaining weight, they are not the sole thing we should be focusing on when it comes to improving our health."

Myth: Eating low-fat food will make you lose fat.

Truth: A low-fat diet doesn't necessarily translate into weight loss.

In an eight-year trial involving almost 50,000 women, roughly half the participants went on a low-fat diet, while the others did not. The researchers found that the women on the low-fat plan didn't lower their risk of breast cancer, colorectal cancer, or heart disease. Plus, they didn't lose much weight, if any. New recommendations show that healthy fats, like those from nuts, fish, and avocados, are actually good for you in moderation. So add them back into your diet if you haven't already.