Really, it shouldn’t be so difficult to figure out which eating regimen will set fire to fat while maintaining muscle. Fortunately, the International Society of Sports Nutrition just released its position paper, which combs through all existing scientific studies to report how every diet will affect your body composition. Here, we’ve pulled five of the most six-pack-friendly diets and streamlined how they’re great, as well as why they might be right (or wrong) for you—according to the hard science.
"Protein is great for fat loss. It helps build and preserve lean muscle tissue and can increase the amount of calories you burn. It’s also a great source of energy that helps you feel fuller for longer, so you’re less tempted to snack. Good sources include chicken breast, tuna, eggs, milk and chickpeas. And if you’re finding it difficult to avoid snacks that are high in carbohydrates, try substituting them for protein shakes or bars. Remember also to opt for the lean sources of protein because some sources can be high in saturated fat."
I’m in favor of any program that promotes whole foods over hyper-processed fare, and this is one thing the popular diet plans can agree on. Overly processed foods have been linked to weight gain, perhaps because many unhealthy packaged foods (think: potato chips, ice cream, frozen pizza, cookies and the like) lack the fiber found in many whole foods, including vegetables. Fiber helps fill us up, and research suggests that by simply adding more fiber to your menu, you can lose weight nearly as well as a more complicated approach. Consistently choosing whole foods is one way to do this.
What the diet advocate says: ‘It essentially means scaling your carbohydrate intake up and down in accordance with your activity levels,’ explains performance nutritionist Liam Holmes (phnutrition.co.uk). He uses the principles of nutrient timing to get elite athletes and CrossFit enthusiasts to their leanest before competitions. ‘The body works harder when it doesn’t have carbs as fuel, so it learns to become a more efficient burner of the fuel once it is there.’
The “insulin causes obesity” hypothesis is easily tested. If you give insulin to a random group of people, will they gain fat? The short answer is an emphatic “Yes!” Patients who use insulin regularly and physicians who prescribe it already know the awful truth: the more insulin you give, the more obesity you get. Numerous studies have already demonstrated this fact. Insulin causes weight gain.
If you want to lose weight, you’d better avoid special “low-carb” products that are full of carbs. This should be obvious, but creative marketers are doing all they can to fool you (and get your money). They will tell you that you can eat cookies, pasta, ice cream, bread and plenty of chocolate on a low-carb diet, as long as you buy their brand. They’re full of carbohydrates. Don’t be fooled.
If you’re trying to shed excess weight, use all three calorie-density-reduction strategies. While this study showed that cutting the amount of fat added to foods was the single most effective way to reduce ad libitum calorie intake, it is clear that all three methods were effective. Furthermore, they are not mutually exclusive, so it is likely that using all three in combination would work even better than each one used alone.
More importantly, though, strength training does wonders for your body. It helps make bones denser, critical because our bones become weaker as we age, increasing the risk of osteoporosis — of the 10 million Americans suffering from the disease, 80 percent are women. (4) Strength training helps build lean muscle tissue, helping you lose more weight all over, including the dreaded belly fat. It also reduces your risk of type 2 diabetes and cardiovascular disease. (5)

The study began with 609 relatively healthy overweight and obese people, and 481 completed the whole year. For the first month, everyone did what they usually did. Then, for the next eight weeks, the low-fat group reduced their total fat intake to 20 grams per day, and the low-carb group reduced their total carbohydrate intake to 20 grams per day. These are incredibly restricted amounts, considering that there are 26 grams of carbs in the yogurt drink I’m enjoying as I write this, and 21 grams of fat in my half of the dark chocolate bar my husband and I split for dessert last night.
High blood sugar levels coupled with high blood ketones, on the other hand, will mean that you have a pathologically low level of insulin – something non-diabetics do not suffer from. This can lead to ketoacidosis – a potentially life-threatening condition. If this happens, you’ll need to inject more insulin; if you’re at all unsure of what to do, contact a medical professional. Coveting really high blood ketones for weight control is not worth the risk for type 1 diabetics.

An advisory committee to the government's 2010 Dietary Guidelines concluded that evidence overwhelmingly shows that diets based on the glycemic index do slightly or no better at weight loss than other types and aren't markedly superior at keeping off pounds already lost. In 2009, the independent, nonprofit Cochrane Collaboration reviewed six small, randomized controlled trials of low-GI diets tested over periods from several months to a year. Overall, low-GI dieters lost about 2 more pounds than comparison diets on average. Researchers found similar results in a study published in the New England Journal of Medicine in 2010. They examined weight-loss maintenance of 773 overweight adults on high- and low-GI diets. After 26 weeks, the low-GI dieters had regained 2 pounds less on average than their high-GI counterparts had.
Whether you’re doing cardio or strength, working out in intervals is the best way to maximize your calorie burn in a short amount of time. Alternate between short bursts of intense effort and periods of lower intensity or rest. The intensity resets your metabolism to a higher rate during your workout, so it takes hours for your body to cool down again. This is what's known as EPOC (excess post-exercise oxygen consumption). That means you burn more calories long after you’ve finished your workout compared to doing a workout at a continuous moderate pace, according to a 2017 study from the European Journal of Applied Physiology.
This could be because the body increases insulin secretion in anticipation that sugar will appear in the blood. When this doesn’t happen, blood sugar drops and hunger increases. Whether this chain of events regularly takes place is somewhat unclear. Something odd happened when I tested Pepsi Max though, and there are well-designed studies showing increased insulin when using artificial sweeteners.

After 30 days on the diet, you’ll slowly add in one of the restricted foods — one at a time and for a few days only — to see how your body reacts. At this point, you can continue just avoiding the ingredients you suspect you’re sensitive to, or go to an allergy specialist to receive confirmation and see if there’s anything else you might be allergic to.
Very low levels of thyroid hormone usually indicate an autoimmune reaction to the thyroid gland itself. This means you’ll have to take thyroid hormone supplements orally, usually the stable form T4 (Levaxin), which your doctor can prescribe for you. Your body will transform this into the active T3 hormone when necessary. The supplement dose should be adjusted so that you reach normal hormone levels (TSH, T3, T4) and sufficiently alleviate symptoms – though a few people feel best when keeping TSH slightly below normal.
The DASH Diet, which stands for dietary approaches to stop hypertension, is promoted by the National Heart, Lung, and Blood Institute to do exactly that: stop (or prevent) hypertension, aka high blood pressure. It emphasizes the foods you've always been told to eat (fruits, veggies, whole grains, lean protein and low-fat dairy), which are high in blood pressure-deflating nutrients like potassium, calcium, protein and fiber. DASH also discourages foods that are high in saturated fat, such as fatty meats, full-fat dairy foods and tropical oils, as well as sugar-sweetened beverages and sweets. Following DASH also means capping sodium at 2,300 milligrams a day, which followers will eventually lower to about 1,500 milligrams. DASH Diet is balanced and can be followed long term, which is a key reason nutrition experts rank it as U.S. News’ Best Overall Diet, tied with the Mediterranean Diet.
When you’re eating to deal with your emotions, like anxiety, stress or unhappiness, you’re likely not reaching for carrot sticks and blueberries, but carbohydrates, processed foods and even alcohol. Those calories eventually add up and, at the same time, you’re avoiding learning how to deal with difficult emotions and situations. It’s pretty much a lose-lose situation.
“Every morning I drink a cup of warm water with half a lemon squeezed into it, a teaspoon of apple cider vinegar, and a dash of cayenne pepper,” says Michelle Keough. This helps her start her day off on a healthy note while getting her hydrated after a long night. This trick, combined with eating meals built around protein and veggies, helped her lose 20 pounds and keep it off.

Obviously, it’s still possible to lose weight on any diet – just eat fewer calories than you burn, right? The problem with this simplistic advice is that it ignores the elephant in the room: Hunger. Most people don’t like to “just eat less”, i.e. being hungry forever. That’s dieting for masochists. Sooner or later, a normal person will give up and eat, hence the prevalence of “yo-yo dieting”.
"Your body needs a healthy balance of exercise and rest. Doing too much prevents the body from shifting excess fat. Exercising without rest can impact our levels of the steroid hormone cortisol and cause an increase of stubborn fat stored in the belly. Not allowing your body to recover can increase the risk of injury too, so make sure you factor in rest days to your plan."
×