Diets, Demystified

Which Popular Diet Plan is Best for You?

The Centers for Disease Control estimates that nearly half of all Americans try to lose weight each year, which means that at any given moment, nearly half the country is on a diet. However, with the internet overloaded with articles and information about dozens of diet trends that promise to deliver results, fast, it can be incredibly difficult to decide what might work best for you. For certain, no diet works unless it is something that fits your lifestyle enough that you’ll stick with it for the long haul. So educate yourself, choose wisely, and understand that a healthy diet doesn’t always have to be extreme. “If you balance each meal with protein, fat and the minimal amount of carbohydrates to feel satisfied and not irritable, you are in a good place,” explains nutritionist Ann Louise Gittleman, PhD, CNS. Here, six popular diet trends are explained to help you decide which – or what combination of which – will help you accomplish your nutritional goals.

The Paleo Diet

Also known as the Caveman Diet, the Paleo Diet is based on the idea of only eating foods that were available to early humans; think hunter-gatherers from 10,000 years ago. To that end, the Paleo Diet emphasizes whole foods, including lean meats, fruits, vegetables, nuts and seeds, and eliminates all grains, dairy, legumes, sugar, alcohol and processed foods. It does allow minimal usage of natural, low-glycemic sweeteners, such as coconut sugar, maple syrup, honey and molasses. “The food groups eliminated in the Paleo Diet are all very inflammatory in this day and age, and they contribute to diabetes, obesity and heart disease,” Gittleman says. “If you suffer from allergies or inflammation, you would do well by eliminating these newer food groups.” Gittleman says the diet of early humans is much better matched to the human body than the way we eat now, and because of that, can work for anyone.

The Ketogenic Diet

The Keto Diet involves drastically reducing your carbohydrate intake and replacing those calories with fat; on this diet, about 75% of your total calories come from fat, 25% come from protein and less than 5% come from carbohydrates. Fats should come from healthy sources like avocados, nuts, seeds, olives and olive oil, coconuts and coconut oil, full-fat dairy, fatty fish and whole eggs. This puts the body into ketosis, a metabolic state in which fat, rather than glucose from carbohydrates, is used for energy. Ketones are made from fat by the liver and sent into the bloodstream to be used by the body as fuel until carbohydrate intake increases. “The Keto Diet is an SOS diet for those who need to lower and balance inflammation or lower their risk of metabolic disorders,” Gittleman says. “It’s good for those who need to lose weight quickly, and for those with diabetes and seizure disorders.” Gittleman notes that many women don’t do very well with such restricted carbohydrate intake, especially during certain times of the month.

The Whole30 Diet

The Whole30 Diet is similar to the Paleo Diet in that it eliminates grains, dairy, legumes, sugar, alcohol and processed foods, but it is more restrictive in that dieters cannot utilize natural sweeteners like honey, agave or maple syrup. The diet, which emphasizes the consumption of vegetables, fruits, unprocessed meats, seafood, eggs, nuts and seeds, is only intended to be done for 30 days, after which foods are slowly reintroduced. However, many people struggle with adding foods back in a balanced way and end up re-gaining the weight they had lost. “The Whole30 Diet is a good diet, but the severity of it often makes it difficult for people to have success long-term,” Gittleman says. “Sometimes, we just need a little sugar.”

The Zone Diet

The Zone Diet is built around consuming a certain amount of carbohydrate, protein and fat at each meal; specifically, 40% carbohydrates, 30% protein and 30% fat. For further customization, a day of food can be divided into Zone “Blocks,” consisting of a specified amount of carbohydrate, protein and fat, and the blocks can be distributed as each dieter sees fit across their meals. While the Zone Diet does not eliminate any foods, carbohydrate sources should be low-glycemic, proteins should be lean, and fats should be from healthy sources. “The Zone Diet is well-balanced and not so severe, and can be beneficial for anyone who wants to lose weight and access stored body fat for energy,” says Gittleman. “It is especially good for athletes, because carbohydrate consumption is less restricted.” Gittleman says carbohydrates are only the enemy when eaten to excess, and that the Zone Diet is also good for women who feel they need more carbohydrates to keep their blood sugar balanced.

Intermittent Fasting

While many diets focus on what you eat, intermittent fasting focuses on when you eat; it is a pattern of food consumption that alternates between periods of fasting and periods of eating, for both weight loss and an improvement in overall health. Common methods include fasting for 12 to 16 hours each day – think about finishing your dinner by 8 PM and then not eating again until noon the next day, or whatever window works best for you - or fasting for a full 24 hours two times per week. During your fasting times, consume only water and zero-calorie beverages like black coffee or tea. During your feeding windows, calories are not restricted. Intermittent fasting works because after hours without food, your body will switch from burning sugar for energy to burning fat.

“Fasting takes the stress off the digestive system and allows us to burn fat for fuel,” Gittleman says. “There is also good research that shows intermittent fasting helps to optimize glucose metabolism, reduce inflammation, reduce oxidative stress and optimize cellular repair.” By contrast, Gittleman says the practice of eating many small meals throughout the day constantly ignites your insulin production, leading to insulin resistance and the metabolic disorders it can cause. She also notes intermittent fasting can be done by anyone, with the exception of those with reactive hypoglycemia, which occurs after eating rather than while fasting, or other adrenal issues.


Both vegetarians and vegans choose not to eat meat and fish, however vegans are much stricter than vegetarians. Veganism also prohibits the consumption or use of any products that come from animals, including milk, eggs, yogurt, cheese, butter, honey, leather goods, wool and silk. While many who choose a plant-based diet opt to give up meat, dairy and other animal products for ethical or environmental reasons, and increasing your intake of vegetables is a great way to take in vitamins, minerals and phytonutrients, Gittleman warns that vegetarians and vegans often fall short of their daily protein needs. Plant-based sources of protein include beans, lentils, quinoa, tofu and tempeh, but attention must be paid to consuming enough, as more by volume is required to meet daily protein goals than would be needed with animal protein sources. “Another issue I see with vegans and vegetarians is they can be eating too much sugar, in the form of too many fruits and carbohydrate-heavy snacks, which creates an insulin situation,” Gittleman says. “If you raise your blood sugar too much, you increase your risk of being overweight and having metabolic syndromes. To really balance your blood sugar, you need the right carbohydrates and the right kind of protein.”