If you've seen Jersey Shore alum Vinny Guadagnino lately, you can tell he's been working out and eating well as he makes his MTV return in Jersey Shore Family Vacation. And if you've been following him on social media, you know he attributes his physique to the keto diet, even calling himself a "keto guido." But what is this trendy diet that he and other celebs (e.g. Halle Berry and Kim Kardashian) swear by?
Like Atkins, the keto diet is all about cutting carbs — with the idea that without carbs, the body will start a process called ketogenesis, breaking down fat into an energy source. Therefore, you can eat meats, leafy greens, above-ground veggies, high-fat dairy, nuts, seeds, and sweeteners; but you have to avoid most grains, sugar, fruit, and root vegetables. "Try to remember that keto is high in fat, moderate in protein, and very low in carbs," a Ruled.me explainer says. "Your nutrient intake should be something around 70% fats, 25% protein, and 5% carbohydrate."
But as Vox points out, the keto diet is based only on a scientific hypothesis, and studies of low-carb diets suggest they don't outperform other diets in terms of long-term weight loss. (In the short term, the keto diet can seem effective because it causes rapid water loss and perhaps even controls appetite.)
Plus, a lot of people have trouble staying on the diet. "Randomized controlled trials don't lie," blogged obesity researcher Stephen Guyenet. "The average person can't even stick with the diet for six months, as judged by urinary ketone levels. The minority of people who find it easy, get good results, and stick with it are the ones who write about it on the Internet."
A few years ago, National Institutes of Health researcher Kevin Hall conducted what's considered the "gold standard" study of ketogenic weight loss and found that the keto regimen didn't burn the pounds as effectively as a higher-carb diet. "The idea is that low-carb, ketogenic diets cause your body to burn way more calories, resulting in a lot of weight loss, even if you eat more than you were eating before," he told Vox. "But our studies, as well as many others, demonstrate nothing of the sort."
Still, Vinny is a huge proponent of the diet, so perhaps he's in the minority of folks who have successfully vetoed carbs and keto-ed themselves into shape. And if he's healthier as a result, more power to him!