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Put down what you’re eating and listen up: Just because a certain snack or diet gets mad props on the Internet doesn’t mean it’s legit. Some food fads are just over-hyped, over-Instagrammed trends that won’t benefit your muscles or your midsection (case in point: juice cleanses). Others are actually science-based with proven health and weight-loss benefits. The key is knowing the difference. So we dug through the research and asked experts to decode 10 top diet trends. Here’s the verdict:
1. Is fasting healthy?
We all know starving yourself doesn’t work (cue cake cravings), but intermittent fasting — as in eating 500 calories one to two days a week or going 12 to 18 hours in a day without food — has been linked to improved blood sugar levels, boosted immunity, decreased risk of heart disease and cancer, increased longevity and weight loss. Plus, fasting spikes levels of growth hormone to protect your hard-earned muscle gains. The idea is that without a constant supply of quick carbs circulating through your system, your body starts to burn fat. There are possible downsides: Restricting calories can cause brain fog and rebound bingeing, but proponents argue that once you get over the hangry hump, it’s easy.
Bottom line: “It definitely has its benefits, but it’s not for everybody,” says Ariane Hundt, MS, clinical nutritionist and fitness trainer.
2. Is Paleo a passing trend?
As you know, cave-man eating includes foods consumed by our hunter-gatherer ancestors: vegetables, seafood, grass-fed meat, eggs, nuts, seeds. “It’s an anti-inflammatory diet based on whole foods, lean proteins and good fats that allows you to maintain muscle mass,” Hundt says. That’s not to say all experts give it a thumbs up: “The diet eliminates foods that offer significant health benefits, including whole grains and legumes,” adds Jackie Newgent, RDN, culinary nutritionist and author of The All-Natural Diabetes Cookbook (American Diabetes Association, 2015).
Bottom line: Paleo shuns junk food in favor of whole foods (nice!), but it’s still a “diet” with restrictions.
3. Are probiotics really a cure-all?
Your gut contains an army of probiotics, healthy bacteria that can affect everything from your energy to your digestion. But will eating probiotics in food form or supplements give you a health boost? “More isn’t necessarily better,” says Rebecca Mohning, MS, RD, registered dietitian and certified sports dietitian. “Different strains of probiotics offer different benefits, so eating a variety of fermented foods is your best bet.” Probiotic supplements are best if you have a weakened immune system, an allergy to dairy or if you’re taking antibiotics — and aim for a broad spectrum, multi-strain supplement with as many as 10 to 12 strains, suggests Rochelle Sirota, RD, CDN, a nutritionist in New York City.
Bottom line: Say yes to fermented foods like yogurt, sauerkraut, kefir and kimchee.
4. Is kelp the new kale?
Kelp has been called ���the most nutritious veggie in the world,” probably because the seaweed is loaded with iodine, manganese, magnesium, iron, calcium and copper. “Seaweed contains a significant amount of minerals that makes it distinctly different from land-based vegetables,” says Newgent. So yes, like kale, it’s a nutritional star, but adding seaweed won’t save you from an otherwise unhealthy diet. (Psst: And don’t assume just because it says seaweed on the label you’re munching on something healthy; reading the ingredient list is still a must.)
Bottom line: Your total diet is more important than a single superfood.
5. Is sugar really as bad as smoking?
Move over, tobacco. A study published in the American Journal of Public Health found that a sugary soda a day could age your immune cells the same as smoking. High sugar intake is also linked to diabetes, heart disease and obesity. “Sugar is evil from the standpoint that it adds a lot of calories without providing any nutritional value,” Mohning says. But that’s not to say you have to totally sideline your sweet tooth. The World Health Organization says to keep your sugar consumption below 5 percent of daily calories, or 6 teaspoons a day.
Bottom line: Skip the sneaky sugars in store-bought sauces and crackers and enjoy it as dessert once or twice a week, Mohning suggests.
6. Can meal-delivery services really deliver?
Who needs to cook when you can get perfectly portioned Paleo, gluten-free, low-sodium, vegan or raw meals delivered right to your door? “It works for people who want to understand what a healthy portion is and for people who don’t get the concept of clean eating,” Hundt says. The downside: It doesn’t teach you how to handle food triggers like eating out, emotional eating or stress eating — “and there’s so much power to cooking,” Hundt adds.
Bottom line: Meal delivery services may be pricey and restrictive, but they can kick-start a healthy eating plan.
7. Can you build muscle on a vegan diet?
You don’t have to eat like a cave man to get enough protein — vegans can build muscle mass, too. “Aiming for 20 grams of protein at each meal is a good minimum goal for active women,” Newgent says. “The key is to have planned, protein-rich vegan foods on hand, such as hemp seeds or quinoa at breakfast, edamame or tofu at lunch, and beans or lentils at dinner.”
Bottom line: Vegan eating isn’t automatically healthy (hello potato chips!) or protein-rich, so plan ahead.
8 . Is full-fat dairy better?
It’s been drilled into us that whole milk is bad and skim milk is good, and on the surface, it makes sense (skim does have half the calories and 40 times less fat), but science disagrees. A review published in the European Journal of Nutrition found that full-fat dairy does not raise your risk of cardiovascular disease or Type 2 diabetes and that if you want to shed pounds, full fat may be your better bet. So what’s the dealio? Fats are important for nutrient absorption and hormone production, plus they can keep you satiated — and away from sugary processed food, Mohning says.
Bottom line: Don’t overdo the saturated fat, but opting for the 2 percent Greek yogurt or a glass of whole milk as a postworkout recovery beverage won’t hurt your heart or waistline.
9. Does bone broth really have health benefits?
Bone broth is a social media darling, but is grandma’s remedy really a cure-all? Granted, there have been no scientific studies specifically on bone broth, but components of the homemade stock, namely cartilage, gelatin, collagen and minerals, have proven health benefits. “Bone broth is anti-inflammatory, helps reduce joint pain and promotes healthy digestion,” Hundt says. Unfortunately, traditional store-bought stock doesn’t cut it; your best bet is to make it from scratch. Bonus: The low-cal brew also doubles as a sports drink, replenishing lost electrolytes without the added sugar and food colorings of Gatorade.
Bottom line: It’s not a magic elixir, but it sure beats sugary processed drinks.
10. Are cheat days legit?
Permission to cheat, granted! A recent study published in the Journal of Consumer Psychology suggests that planned splurges can actually motivate you to stick to your diet goals long term. What’s more, treat meals make your body produce leptin, a feel-full hormone that helps your body burn fat. Not that you have permission to eat everything in sight: “Don’t eat until your digestive system is thrown off and your energy level drops hard,” Sirota warns.
Bottom line: Cheat days can boost self-control — just don’t go cray cray.