We've been 'eating healthy' all wrong for decades

Ever wandered down the 'health foods' isle of your local grocery store?

If it's anything like the one near me, it's full of "low-fat," carb-heavy snack foods.

Here's the problem: For many of us, low-fat diets don't work.

Why? Because our bodies also need fat, protein, and fiber to function properly. And when food companies remove the fat from their ingredients, they substiute them with another, more nefarious one: Sugar.

As far back as 1972, British professor of nutrition John Yudkin warned that sugar - and not fat - was the greatest danger to our health, a recent story in The Guardian points out. But his findings, summarized in a book called "Pure, White, and Deadly" were widely criticized; he was all but discredited.

Instead, fat became the enemy.

The problem with a 'low-fat,' high-sugar diet

All carbohydrates - bread, cereal, or potatoes - are ultimately broken down into glucose, which circulates in our blood and gives us energy. Sugars get broken down quickly and tend to raise blood glucose the most dramatically.

Many foods that naturally contain sugars, like fruit and milk, are also rich in other nutrients including protein and fiber. Protein helps build strong muscles; fiber helps keep us feeling full and helps regulate digestion.

But these so-called "health foods" typically don't have any of those. This is the reason they're called "empty carbs" - they don't keep you full and instead can actually make you feel more hungry.

Most of the calories we're getting from sugar are coming from processed foods. According to the CDC, two-thirds of all the calories Americans get from added sugars come from processed foods like snack bars, breads, and cakes. The other third are from soda and sugary drinks.

How demonizing fat led us to products stuffed with sugar

Fat-restricting dietary guidelines went into effect in the US in 1977; most of them are still in effect today, including the suggestion that we restrict our intake of saturated fat to under 10% of all the calories we consume in a day and that we limit our calorie intake from all fats to 20% to 35% of what we eat in a day.

But several recent studies, including one published last year in the BMJ journal Open Heart, challenge those guidelines, with some even going so far as to say there may not have been evidence to support coming up with them in the first place. An eight-year trial involving almost 50,000 women, roughly half of whom went on a low-fat diet, found that those 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.

Nevertheless, prevailing ideas about dangerous fats and oils continue to dominate the food industry.

In the 1980s and '90s as food makers from yogurt companies to candy giants scrambled to remove fats from their products, they began compensating for the loss of those creamy, rich flavors with sweet, sugary ones.

Now, syrupy yogurts, cereals, and snacks are emblazoned with bright blue "low-fat" labels. Even some packages of candies, like Twizzlers and Lemonheads, say "fat free." Yet the sugar content of these foods is astounding, especially when you take into consideration the recent FDA standards which say we should eat no more than 50 grams of sugar per day.

Here are a few examples:

• A 6-ounce serving of Horizons Organic fat-free vanilla yogurt: 35 grams of sugar
• A serving of "fat-free" Twizzlers or Lemonheads candy: 20 grams of sugar
• A Wendy's apple pecan chicken salad: 40 grams of sugar

What's the solution?

Dozens of new studies support the idea that healthy fats, like those from nuts, fish, and avocados, are good for us, so long as we eat them in moderation. So add them back into your diet if you haven't already, and look to cut back on your intake of refined carbs and sugary snack foods instead.

These basics are a good place to start:

• Keep vegetables as the cornerstone of your meals. Or, in the words of famous journalist and food writer Michael Pollan, "Eat food. Not too much. Mostly plants."
• Snack on nuts: Since they're high in protein, nuts can help stabilize blood-sugar levels - which, if they plummet, can make healthy people feel hangry and is especially dangerous for people with diabetes. Nuts are also a good source of fiber, a key nutrient that helps aid digestion and keeps us feeling full.
• Cut back on added sugar and refined carbs. Diets that are high in sugar and refined carbs (white rice, sweet snack foods, white bread) and low in whole grains (brown rice, whole wheat) have been linked with health problems, while diets high in whole grains and low in refined carbs tend to be linked with more positive outcomes.
• Incorporate oily fish like salmon into your diet. Salmon is rich in Omega-3 fats, which help protect our cell membranes, the structure protecting the inner components from their outside environment. They're also the building blocks of the hormones that regulate blood clotting and inflammation.
• Eat avocados. While they're high in fat and calories (just half of one packs 120 calories, about the equivalent of a slice of bread), avocados are low in sugar and rich in fiber. So add a few slices to your next meal.

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