The idea of the “diet” has changed over the years. It used to be about cutting back calories to lose weight. Now a diet is more about food quality and boosting overall health.
I’d say that’s a good switch of focus. No one wants to slice calories every day so they feel dizzy and hungry.
Rather, they want to eat nutrient-dense, satiating food that not only helps them lose weight but has the potential to improve heart health, lower blood sugar, reduce inflammation, and more. The Mediterranean and DASH diets are great examples.
But there is another eating style that’s generating a lot of buzz and has plenty of science to back it up: intermittent fasting. The general idea is instead of eating throughout the day, you would have designated six-to-eight hour feeding windows.
Two common forms of intermittent fasting are the 8:16 and 5:2. 8:16 assumes the structure outlined above, while the 5:2 takes a different approach. That strategy encourages participants to eat normally five days per week, but make drastic restrictions two days per week.
Thus far, research has found big benefits to both approaches. The benefits are believed to be tied to a process called “metabolic switching.” The process is when your metabolism switches energy systems: it runs out of stored glycogen so it uses fat.
Because people eat so frequently throughout the day and refill glycogen stores, this switch almost never occurs. And this seems to be detrimental.
Metabolic switching is associated with improved cell health, increased fat burning, weight loss, lower blood sugar, and lower blood pressure.
Studies on both animals and humans have shown that intermittent fasting can decrease resting heart rate and blood pressure. It can also improve blood lipid levels, reduce inflammation, and modify risk factors associated with heart disease and type-2 diabetes.
Research has also shown intermittent fasting can have positive results on cognitive function and memory.
One study compared the health effects of a traditional calorie-restricted diet and a 5:2 diet. Although both groups lost the same amount of weight over the trial period, the 5:2 group showed greater improvements in insulin sensitivity and lost belly fat.
If you want to find a diet that improves overall health and not just encourages weight loss, an intermittent fasting diet could be worthwhile. Eating healthful foods, like those in a Mediterranean diet is recommended, and will likely provide optimal results.