The old adage “abs are made in the kitchen” is actually pure fact. The proof is in the homemade protein powder pudding. Research published in the Journal Of Obesity. in 2012 showed that women, age averaging 58, who adopted healthy dietary habits alone over a yearlong period had an 8.5% weight reduction. Those who just exercised lost 2.4% body weight, and women who combined both lost 10.8% body weight.

Yet sticking to your diet, or figuring out which one is right for you, can sometimes seem tougher than maintaining an exercise regimen given the dizzying number of diets to sift through. Only a handful of great diets have stood the test of time when it comes to delivering successful long-term weight loss.

Among the top result getters are ketogenicgluten-freePaleoMediterranean, and If It Fits Your Macros diets. We asked the experts which ones are best for active women who are looking to optimize their weight loss and ultimately lead a longer, healthier life.

Ketogenic Diet

The principle behind the ketogenic diet: By limiting the number of refined carbs in your diet to below 100 grams daily and raising the level of healthy fats you eat while still consuming moderate protein daily—with a typical macronutrient ration of 75% fats, 20% protein, and 5% carbs, your body becomes trained to utilize free fatty acids as an energy source. That leads to greater fat burn and puts your body in a state of ketosis, producing a substance called ketones, which your body then uses for fuel rather than carbs or protein.

Proponents of this diet say it helps you burn fat fast, plus it can help retain muscle and reduce hunger. The classic ketogenic diet uses prescribed meals to meet the low-carb, adequate protein, high-fat, calorie-restricted diet. The more recent medium-chain triglyceride (MCT) ketogenic is more flexible and calculates roughly the amount of MCTs (though you’ll need some long-chain triglycerides, or LCTs) needed to maintain energy levels. A coconut ketogenic diet focuses specifically on MCT fatty acids from sources like coconuts. Advocates say MCTs are prefered over LCTs like butter or canola oil, because MCTs generate more ketones per unit of energy than LCTs, helping to maximize fat loss in a relatively short period of time. Note that if you’re following this plan, choose coconut oils rather than products sold in stores as “MCT oil.” That form of MCT oil is an isolated MCT called lauric acid, which behaves more like an LCT in the body.

There are three ways to get your carbs on a ketogenic diet: With a cyclical approach, you’ll have five low-carb days and one “refeed” day when you can have as many carbs as you want. Targeted means consuming 25 to 50 grams of sugar only before exercise, then limiting carbs the rest of the day. On a standard plan, you’ll just have 25 to 50 net carbs daily. The challenge, explains Josh Axe, a clinical nutritionist and doctor of natural medicine, is to find the right macronutrient balance to keep you in the keto zone: Too much protein and your body won’t stay in ketosis; too little and you’ll lose muscle mass. Too many fats and you’ll gain weight; too few and you’ll have no energy. Axe recommends following a coconut ketogenic macro plan that is 70% fat, 20%protein, and 10% carbs. That will help deliver results in just one month—but don’t stay on it too much longer, he warns. Research in the International Journal of Sport Nutrition and ExerciseOpens. Metabolism found that ketogenic diets can lead to a decrease in fat-free mass, or skeletal muscle, so you’re best off cycling off it after 30 days.

One big benefit is that this diet won’t leave you feeling as sluggish as other low-carb plans. Think of MCTs as a cleaner-burning fuel than sugar. A study in the Journal of Exercise Rehabilitation found those on a keto diet for three weeks were able to complete sprints faster and were also less fatigued after weight loss compared with the non-ketogenic diet group.

Gluten-Free Diet

This latest food trend goes against the grain. Gluten-free. diets eschew wheat, rye, barley, and sometimes even oats for things like buckwheat, rice, quinoa, and millet. Why all the fuss? A protein in gluten-containing products may aggravate your digestive system and other vital organs and may even throw off hormones. “Grain sensitivity can create severe inflam- mation, leading to hormone imbalances that promote the double whammy of fat gain and muscle loss,” says Peter Osborne, D.C., a clinical nutritionist and author of No Grain, No Pain. 

“‘Grainflammation’ can decrease your ability to break down, digest, absorb, and assimilate the nutrients from your food,” Osborne explains. New research published in the International Journal of Obesity. found that consumption of gluten-containing products caused more weight gain compared with when they were not consumed, with similar calories allotted. Some of the inflammation mechanisms also impact cortisol and insulin, which regulate inflammation and fat storage, leading to a reduced capacity to generate energy, burn fat, and build muscle, Osborne adds.

So, what’s off-limits besides most cereal, bread, pasta, and processed foods? Turns out, a lot of foods can create allergic reactions, leading to inflammation. Even dairy products contain gluten cross-reactors. Also look out for casein, coffee, and oats(which are often crossbred with wheat). Here’s what you can eat: fresh organic vegetables, grass-fed meat, wild-caught fish like salmon, berries, and nuts. Some other options may include sprouted products (like sprouted oat, spelt, corn, or coconut flour)because of their ability to break down phytic acid, which binds nutrients and keeps them from being absorbed. Also thumbs up are wild rice, buckwheat, brown rice, gluten-free oats and corn, germinated/ sprouted brown rice, sweet potatoes, butternut and spaghetti squash, and quinoa.

If you want to go gluten free, stick with it for about a month. If you feel a difference, try reducing foods with cross-reactors to find your best balance within this diet.

Paleo Diet

The premise of the Paleo diet is to eat like your caveman ancestors. That means valuing healthy fats, loading up on veggies, cutting out carbs, and focusing on naturally raised meats. The diet, wildly popular among athletes, may help preserve and even increase lean muscle since it focuses so heavily on animal protein, incorporating it in each meal—with some recommendations targeting 1 to 1.5 grams of protein per pound of body weight per day. Spreading protein intake throughout the day may have muscle-building advantages: A study published in 2014 in the Journal of Nutrition indicated that including a moderate amount of protein at each meal better assists muscle-protein synthesis over 24 hours compared with having it in selected meals.

This muscle-friendly diet also eliminates some plant-based foods (legumes, grains, beans, and lentils), so dietary lectins—proteins bound to carbs, cells, and tissues that are resistant to digestive enzymes— are heavily reduced. These lectins attach to the lining of the stomach, allowing other undigested proteins to enter, which can result in decreased energy and weight gain. A review done by the Journal of Cereal Science indicated that dietary lectin affects weight gain via leptin resistance. Leptin is a hunger hormone that sends a signal to your brain that you’re full.

Certainly, eliminating processed foods that wouldn’t be found in any cave can only help with weight-loss efforts. “Choosing whole foods over processed ones has been linked with a reduction in visceral fat (belly fat) and blood pressure and a decreased risk of disease such as heart disease, type-2 diabetes, and cancers of the colon,” says Erin Palinski-Wade R.D., C.D.E., author of Belly Fat Diet for Dummies.

True Paleo veterans opt to be dairy-free, but some include it, citing the health benefits of dairy. These go beyond bone-boosting calcium to also include the probiotics found in foods like kefir and yogurt, which are essential for maintaining gut and overall health. “Although some people remove dairy from the Paleo diet, I would recommend consuming two servings of low-fat dairy daily to gain the associated benefits,” says Palinski-Wade. Dairy in the Paleo diet can be optional, based on a person’s preference. According to U.S. News & World Report, those who don’t consume dairy only obtain 700 mg of calcium from a Paleo food plan. The RDA for calcium is 1,000 to 1,300 mg.

Another benefit for those of us who live busy lives is that Paleo diets are actually relatively easy to follow, even when dining out. Choose a lean protein and vegetables, such as broiled fish with steamed vegetables. End your night out with a bowl of fruit.

Mediterranean Diet

It’s not one of the most popular training diets, but it should be, and not just because it’s so heart healthy. The Mediterranean diet is considered anti-inflammatory due to the high consumption of healthy fats, which can positively impact the post-workout recovery process. And according to a 2013 study in the European Journal of Clinical Nutrition, the diet promotes a lower bodymass index in women who are premenopausal.

Healthy fat is key in this diet, with most tables replacing butter with extra-virgin olive oil The diet often exceeds U.S. dietary guidelines regarding this macro, but keep in mind that the oil is considered a healthy fat, rich in monounsaturated and omega-3 fatty acids— both of which are capable of reducing cholesterol and triglyceride levels and helping reduce inflammation that is typically caused by an intense workout.

“The process by which omega-3s can help decrease recovery time is thought to occur through the production of anti-inflammatory molecules and a decreased production of inflammatory proteins. Also omega-3s can significantly shorten the time for fatigued muscles to recover by assisting in converting lactic acid to water and carbon dioxide,” says Charlotte Martin, R.D.N-L.D.N., a corporate dietitian for Medifast.

The Mediterranean diet recommends eating fish twice a week and limiting red meat to only a few occasions during the month. The diet also encourages eating plant-based food like vegetables, fruits, whole grains, and legumes, and suggests other beneficial sources of protein, including nuts, beans, and seeds. (Walnuts contain more omega-3 fatty acids than any other nut with 2.5 grams per one ounce serving.) Plus, these foods are a great source of fiber. Just remember to avoid eating too much fiber-rich fare around your workouts since it can cause gas, bloating, and/or stomach discomfort.

IIFYM Diet

If it fits your macros (IIFYM), also known as flexible dieting, is trending. It’s loved by those who are serious about training because it simply focuses on three metrics: carbs, protein, and fat. But this diet isn’t without controversy since junk food like Pop Tarts, ice cream, and other processed fare is still allowed. It brings up the debate of whether a calorie is really just a calorie regardless of the macro configuration. A review published in 2011 in the journal Appetite indicated that flexible dieting led to more success than restrictive diets, with those who practiced flexible diets reporting a lower BMI, reduced food cravings and few occurrences of binge eating. While IIFYM supports diversity within the diet, it’s vital that a majority of your food choices are whole foods and not junk.

To get started there are a few things you need to know: 1) your fitness goal (lose fat, lose inches, gain muscle, etc.), 2) your total daily energy expenditure, or the amount of calories you burn in a day; and 3) your basal metabolic rate (BMR)—the amount of calories you burn at rest. (To find your BMR, go to bmrcalculator.org or healthstatus.com) Then determine how active you are. If you’re lightly active, you’ll want to multiply your BMR by 1.3; moderately active: BMR times 1.5; and very active: BMR times 1.7. Once that’s calculated, you should have a number that yields kilocalories, which is your total daily energy expenditure. Last, find your ideal macro split; a 40/40/20 macro split is fairly popular with this diet, 20 percent being fat. However, if you find that it’s hard to attain this split, then consult with a registered dietitian, who can help you personalize it.

To help you keep track of your macros while on the go, check out MyFitnessPal, which allows you to easily log meals and contains a bar code scanner. The app will give your calorie intake and the day’s nutrient breakdown. Another popular app, My Macros+, allows you to save macro goals, such as curbing your carbs. The app also determines how much of each nutrient you have left for the day.

BY CAT PERRY AND COURTNEY ANAYA

By MFH