New research studying carb intake in relation to mortality confirms that contrary to popular belief and previous studies, too few carbs — as well as too many — can be harmful to your health. In fact, the National Institutes of Health–funded study, touted as the largest ever of its kind and published in September in the medical journal The Lancet, suggests that low- and high-carb diets could shorten life by up to four years.
This calls into question the validity of low- or no-carb ketogenic diets.
Though the study found that both diets with a high and low percentage of carbohydrates were associated with increased mortality, and a midrange of 50 to 55 percent carbohydrate intake held the least risk, it’s too simplistic to say that too many carbs is too much, too few carbs is not enough, but this many carbs in the middle is just right. What really matters, says the lead researcher on the study, Dr. Sara Seidelmann in the Department of Medicine at Brigham and Women’s Hospital in Boston, is the kinds of carbs you’re eating — and what you may be substituting instead — not just the amount you’re consuming.
Dr. Seidelmann is adamant that the study is not saying all low-carb diets are bad. “Vegetables contain carbs and carry so much of our fiber, and typically when people eat low-carb diets they tend to increase their meat intake. Then,” she says, “their intake of fiber and nutrient-rich and vitamin-rich vegetables may go down, and at the end of the day a person’s nutrition is about what they are eating and not about what they’re not eating.”
If you’re going to cut carbs, you should consider substituting them with better plant-based fats and proteins, not animal-derived fats and proteins.
Dr. Seidelmann goes on to explain, “We’re not an anti-low carb study. That’s not the case. You need to just be mindful, because the typical eating patterns in the U.S. and Europe are that when people eat fewer carbs they tend to increase meat consumption. Whereas if you’re going to cut carbs, you should consider substituting them with better plant-based fats and proteins, not animal-derived fats and proteins.”
Think of it this way: If you want to eat high protein/low carb, instead of eating a beef burger with a bacon wrap, hold the bun, it’s better to have a veggie burger with a lettuce wrap.
Internist Dr. Keith Roach, who teaches clinical medicine at Weill Medical College of Cornell University and is an associate attending physician at New York-Presbyterian Hospital, agrees. “The ketogenic approach that we must get rid of carbs is just wrong. Those who eat the least amount of carbs have the highest mortality,” he says. “And if you eat a lot of carbs, you’re not doing well either. So, yes, it’s better to be Goldilocks and be eating a middle amount of carbs — and make sure they’re plant based and complex sugars, not simple sugars.
“Simple carbs — things like table sugar (natural or chemical sugars), maple syrup, and even honey — should be consumed only in spare amounts,” Dr. Roach says. “They are a big sugar load to the pancreas and don’t make us feel full. Complex carbs, on the other hand, are starches — things like pasta, potatoes, rice — that in nature come along with fiber and little bit of protein. So you want your starches to be whole-grain starches, because the little bit of fiber and protein slows down absorption and tends to make you feel more full because fiber is a bulk-forming agent in the gut.”
If you want to eat high protein/low carb, instead of eating a beef burger with a bacon wrap, hold the bun, it’s better to have a veggie burger with a lettuce wrap.
Both Dr. Roach and Dr. Seidelmann advise people to eat mostly vegetables, legumes, whole grains, and fruits. “Sure, fruits have some simple sugars,” says Roach, “but they have lots of fiber, so it doesn’t spike your sugar up as if you’re sucking it down from a honey bottle.”
Dr. Roach says that if you manage carbs with a whole-foods, plant-based diet, you’re likely to half your caloric intake. “But,” he says,” I tell people, ‘I don’t care about your weight.’ So many people who focus on weight and weight loss have tried and failed. I tell them, ‘I want you to control the kinds of things you eat.’”
Bottom line there’s no need to eliminate carbs, but you do need to rid your diet of simple sugars and processed foods, and eat more whole fruits and veggies.