Don't believe it.
The review, published Monday in journal The Annals of Internal Medicine, called recent warnings to cut sugar exaggerated and said they are based on weak evidence.
"Guidelines on dietary sugar do not meet criteria for trustworthy recommendations and are based on low-quality evidence," the authors write in their review.
Yet those authors all have links to the food and sugar industries, a New York Times investigation revealed. One of them, Joanne Slavin, sits on the scientific advisory board of Tate & Lyle, a leading global supplier of high-fructose corn syrup. In addition, the study's primary source of funding was a Washington, DC-based group that receives money from companies including Coca-Cola, General Mills, and Hershey's.
None of this is new, however.
In September, a searing Times report revealed that an American trade group called the Sugar Research Foundation paid three Harvard scientists the equivalent of today's average American yearly income to publish a review of heart health studies that made sugar look less unhealthy than it really is — and to paint fat as the villain instead.
The review, originally published in 1967, featured a handful of studies The Times alleges were cherry-picked by the sugar group.
"They were able to derail the discussion about sugar for decades," Stanton Glantz, a professor of medicine at the University of California at San Francisco who researched the sugar industry's impact on our understanding of health, told The Times.
As an American who recently moved to the UK and grew up at the height of the low-fat diet craze, I find this infuriating. At the same time, I'm not surprised: Dozens of registered dietitians, public-health experts, and obesity researchers I've spoken with in the US over the past few years have repeatedlytoldmethat the sugar in our diets is far worse for us than the fat.
Even though I grew up in California with two health-conscious parents, our kitchen was still subject to the anti-fat frenzy. Our fridge was always stocked with margarine, not butter; low-fat products (rather than low-sugar or no-sugar-added ones) ruled our pantry. Even today, if I were to take a walk down the "health foods" aisle of my hometown grocery store, I'd most likely find its shelves teeming with low-fat (high-sugar) foods.
The good news is that we're finally uncovering the truth.
We now know, for example, that, for most people, cutting fat from our diet not only fails to help us lose weight — it also doesn't slash our risk of heart disease. 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. Another recent study took a look at what would happen if people swapped the calories they were getting from specific types of fat with calories from simple carbohydrates (sugar) and found that the change had zero observable health benefits.
Excess sugar, on the other hand (especially in the form of soda) has been linked with several negative outcomes, including weight gain and obesity. A systematic review of 50 years of studies published in the American Society for Clinical Nutrition in 2006 found a link between the amount of sugar-sweetened beverages people consumed and weight gain and obesity.
"The science base linking the consumption of sugar-sweetened beverages to the risk of chronic diseases is clear," the authors wrote in their paper.
Why sugar is the real culprit when it comes to weight gain
When we eat large amounts of sugar and don't balance these calories with those from protein and fat, which the body breaks down more slowly, it can lead to dramatic rises and drops in blood sugar. These "crashes" can cause "hanger," or what's known as being angry and hungry at the same time.
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 most dramatically. And, according to the Centers for Disease Control and Prevention, most of the calories that Americans are getting from sugar are coming from processed foods like cereals, granola bars, breads, and cakes.
Eat more fats — but make sure theyre the right kinds
For the paper in which researchers looked at the effects of swapping calories from fat with those from sugar, researchers studied the eating habits of more than 126,000 people who submitted health questionnaires every few years for up to three decades. Next, the authors tested what would happen if those people swapped out 5% of the calories in their diets from saturated fat (the types of fats most often found in meat and dairy products) with one of three other things: A) calories from simple carbohydrates like sugars and refined grains; B) calories from monounsaturated fats, like the kind found in avocados and olive oil; or C) calories from polyunsaturated fats, like the kind found in oily fish and nuts.
Not surprisingly, the first option — replacing the calories from saturated fats with calories from simple carbs — was not linked with any observable health benefits.
But the second and third options appeared to be connected with several healthy outcomes. Overall, swapping calories from saturated fats with calories from monounsaturated fats, like the kind found in avocados and olive oil, was linked with a 27% decrease in death of any kind as well as lower rates of heart disease, cancer, and neurodegenerative disease.
This is in line with dozens of recent studies supporting 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.