Fad diets come and go like the seasons. Many offer unrealistic or unsustainable claims of rapid fat loss, increased lean muscle mass, youthful skin, and more. However, some popular diets are actually based on sound science and informed by the latest advances in the field of nutrition. Here we describe a few of the better ones and some of their benefits and drawbacks.
Sometimes referred to as semi-vegetarianism, the flexitarian diet emphasizes plant foods and also includes moderate amounts of meat. This diet offers many of the health benefits of plant-based eating, such as plentiful amounts of fiber, essential nutrients, and antioxidants, and decreased risk of heart disease, type 2 diabetes, and potentially, cancer.
The flexitarian diet is less restrictive than a vegetarian or vegan diet, which means it could be easier to maintain long-term. However, this diet may hide or promote disordered eating habits in those who are prone to binge eating, according to one study.
It’s advisable to transition to a flexitarian diet in stages, gradually reducing meat consumptions and increasing plant foods until you reach a maintenance of about 9 ounces of meat per week. Also, as with any diet that restricts animal products it’s important to monitor your levels of vitamin B12, zinc, and calcium when on a flexitarian diet.
Can the famously healthy Mediterranean diet even be any healthier? Why, yes, it can – by making it even greener! The green Mediterranean diet bumps up the plant foods and reduces the red meat content of the regular Mediterranean diet. By so doing, it derives even more heart- and metabolism-enhancing benefits. This diet includes an abundance of fruits, veggies, nuts, whole grains, beans, legumes, herbs, and spices, and of course, liberal amounts of olive oil. In place of red meat, you can enjoy seafood and fish two or more times per week, along with small amounts of eggs, poultry, and dairy.
A randomized trial found that the green Mediterranean diet edged out the regular Mediterranean diet in most health metrics, including 45% better LDL cholesterol-lowering ability, 40% reduction in insulin resistance, 28% better blood pressure-lowering benefits, and twice as much inflammation-fighting power. Both diets provided similar weight loss benefits.
Intermittent Fasting (IF)
In theory, IF and other diets centered around windows of time when you can and can’t eat lead to less calorie consumption, help regulate blood sugar, and improve heart health.
- The 5:2 Plan
A popular way to practice intermittent fasting is to restrict calorie consumption to 25% of normal daily intake on two days per week. In a study of people with type 2 diabetes, this eating style yielded about the same weight loss and blood sugar control benefits as cutting back on calories every day, while also feeling less depriving.
- Time-Restricted Eating (TRE)
This approach creates a feeding window of 12 hours or less per day. Often the window is gradually reduced in order to increase the desired health benefits. In terms of weight loss, both your food choices and the timing of your main meal can have an influence on a TRE diet. Eating predominantly high-calorie foods during the feeding window or eating the bulk of your calories later in the day can each curtail weight loss benefits.
- Fasting Mimicking Diet
Designed to emulate water fasting, while being safe and accessible for most people, this diet tricks your body into thinking it’s fasting. The 5-day calorie-restricted program is plant-based and low-sugar and can be repeated as often as every two weeks. It has been shown to promote weight loss and decrease metabolic syndrome risk factors.
This diet emphasizes animal protein and fat and limits carbohydrates to a maximum of 50g per day. Benefits include slow, steady energy and increased satiety due to its low-carb, high-protein, and high-fat profile. Increased satiety can lead to less calories consumed and many people report rapid initial weight loss on a ketogenic diet.
Conventional wisdom is that the high-saturated fat content of this diet can lead to increased levels of LDL cholesterol and increased risk for cardiovascular disease, and its lower amounts of phytonutrients reduces the cancer-preventive benefits derived from plant-based diets.
Additionally, the keto diet can be difficult to adhere to long-term because it is so low in carbs. A compromise is the Atkins diet, which starts with an induction phase of 20 grams of carbs per day and gradually works up to a maintenance level of up to 100 grams per day. In a study that compared Atkins (55% of calories from fat) to a low-fat diet in obese women, Atkins yielded significantly greater improvements in gut microbiome and antioxidant levels.
When choosing a diet, keep in mind that dietary needs vary among individuals and change with each stage of life. Consult your doctor for guidance before switching up your diet.