Diet

What's better for you, low carb or low fat?

Naturopath Natasha Turner looks into the real health benefits of low-carb and low-fat foods

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Take a stroll through the health and wellness section of any bookstore, and you’ll notice that many of the tomes on display are devoted to one of two ways of eating: low-carb or low-fat. Both have their merits and their downfalls, so which is the right approach to weight loss for you? Let’s get to the bottom of it.

Cutting carbs
The premise behind low-carb diets (think Atkins and South Beach) is that limiting breads, pasta, starchy veggies and fruit can help you shed pounds by keeping your insulin levels in check. Insulin is the hormone that regulates how much sugar is absorbed by our cells to be used as fuel. These sugars are later stored as fat if they aren’t used as energy. When your insulin levels remain steady, your body is more likely to burn stored fat for energy. Sounds good, right? But an ultra-lowcarb diet has its drawbacks. Let’s not forget that carbs give us energy and boost our moods, so some people may find they feel unusually tired and irritable when they cut carbs. And because healthy carbs like vegetables and fruits are a rich source of fibre, restricting them causes constipation and other digestive issues, as well as nutrient deficiencies.

Skimping on fat
The basic rationale behind a low-fat diet doesn’t seem like much of a stretch: Limit fat, lose fat. Since fat has nine calories per gram, as opposed to protein and carbs, which have only four calories per gram, it’s thought that reducing your fat intake is an easy way to cut calories and drop a dress size. Here’s the “but”: Too often, products labelled “low-fat” are laced with sugar and other sweeteners to make them taste better, so low-fat doesn’t necessarily mean low-calorie. Also, low-fat diets are often hard to follow in the long term, because fat helps us feel full and satisfied. And if you’re constantly hungry and plagued by cravings, your diet is going to be tough to maintain. Removing “good” fats from your diet can also negatively affect your cholesterol and hormone levels, since fats are a necessary building block of these essential compounds. Finally, healthy fats help control your appetite and reduce cravings.

The verdict: Follow a balanced approach
A 2010 study in the Annals of Internal Medicine compared low-carb and low-fat diets and discovered very little difference between the two when it came to weight loss. Low-carb dieters did drop more pounds in the first three months, but two years later, dieters from both groups had evened things out with an average weight loss of about 15 pounds. Researchers found the main difference between the two diets lay in cholesterol levels: Low-carb dieters had a 20 percent increase in HDL (good) cholesterol after six months — more than twice the increase of the low-fat dieters. But the problem with eliminating (or seriously restricting) any one food group is that it’s very hard to sustain in the long term. Even better than depriving yourself by cutting carbs or fat from your diet is following a more varied strategy. In an ideal world, your food intake — at every meal — would comprise 35 percent carbohydrates, 35 percent protein and 30 percent fat. If you’re trying to lose weight, start by eliminating unhealthy fats (like saturated and trans fats) and bad carbohydrates (including sugar, white flour and anything processed). Keep enjoying a balance of good fats, carbs and protein. We need fat (healthy sources include olive oil, nuts and avocado) for vitamin absorption and to help us feel full; we need good carbs (whole grains, fruits and veggies) for energy and to improve our moods; and we need protein (meat, fish, dairy and beans) for healthy nerve and muscle function — so a balanced approach is best.

Natasha Turner, N.D. is a Toronto-based naturopathic doctor and founder of the Clear Medicine wellness boutique. She is also the author of the bestselling book The Hormone Diet