The Mediterranean diet was named the best diet for 2021. Here's how to try it.

• The Mediterranean diet has been ranked the best for overall health by experts for four years in a row.
• The eating plan is easy to follow and not restrictive, focusing on healthy fats, produce, and whole grains.
• Here's how you can incorporate Mediterranean style eating into your diet, for benefits such as weight loss, better blood sugar control, healthier digestion, and lower risk of disease.

For the fourth year in a row, the Mediterranean diet has been ranked the healthiest way of eating by dietitians and doctors.

The nonrestrictive, mostly-plant based eating style has been extensively researched, with study after study finding benefits for weight loss, lower risk of diseases, better digestion, and even healthier aging.

The diet is based on eating habits in regions like Greece and southern Italy. These areas of the world are among the so-called blue zones, regions of the world where people tend to live the longest, healthiest lives.

If you're looking to try this celebrated diet for yourself but don't know where to start, dietitians recommend gradually incorporating more Mediterranean-style foods into your diet, including leafy greens, healthy fats, seafood, and whole grains.

At the same time, you can start cutting out foods that some of the healthiest communities in the world tend to avoid, such as refined grains and starches, added sugar, and processed meat.

Swap out processed and red meat for fish or beans

One of the major differences between the Mediterranean diet and the standard American diet is that the latter tends to contain more red meat and processed meat, both of which are linked to long-term health risks.

Research has found that cutting back on red meat and processed meat can lower your odds of having illnesses such as heart disease and cancer.

Read more: How to kickstart healthy eating with this 1-week Mediterranean diet meal plan recommended by a registered dietitian

For instance, you might have a serving of grilled fish, such as salmon or tilapia, with a side of sauteed greens or a garden salad.

You can also use canned beans as an affordable and fiber-rich source of protein, dietitians recommend.

Eat your greens (and reds, and yellows)

Fresh produce is a foundation of the Mediterranean diet, from leafy greens to juicy grapes to bright tomatoes and peppers. These plant foods are high in vitamins as well as fiber, which is important for good digestive health.

Colorful Mediterranean-style salads, stews and pasta dishes aren't just delicious and eye-catching, they're also rich in a variety of nutrients, too.

Different colors can signal different levels of phytochemicals, or plant-based compounds with important nutrients and health benefits.

For a well-rounded diet, aim to eat at least three colors every day from various sources, registered dietitian Brigitte Zeitlin previously told Insider.

Add olive oil

The Mediterranean diet focuses on fat sources like olive oil, which are unsaturated fats that research tells us are better for long-term health and longevity.

Unlike saturated fat, which has been linked to higher risk of heart disease and other chronic illness, unsaturated fat can reduce inflammation.

It's also better for cholesterol levels, and hasn't been linked to metabolic dysfunction or cardiovascular disease.

Healthy fats from both olive oil and fatty fish can help replaced the unhealthy processed oils and fat substitutes that gained popularity in American diets during low-fat diet crazes in the past decades.

Cut back on refined carbohydrates

While the Mediterranean diet doesn't restrict any specific foods, one thing you won't find much of is refined starches and sugary treats.

The diet discourages consumption of added sugars and processed carbohydrates, including snack cakes, candy, potato chips, and the like, in favor of whole foods.

Read more: Eating processed foods can increase your risk of early death from heart disease by 58%, study finds

That may explain why the Mediterranean diet is linked to benefits for blood sugar control and insulin sensitivity, and can be helpful for people with diabetes.

Enjoy wine in moderation

Part of the popularity of the Mediterranean diet is that it allows some indulgence in foods you enjoy, including rich cheeses and yes, even wine. And there are some anti-inflammatory benefits linked to drinking wine, in small amounts.

However, dietitians warn against over-indulging even with red wine, since regularly drinking alcohol has been shown to increase the risk of cancer and stroke.

And if you abstain from alcohol already, there's no reason to start drinking it as part of the Mediterranean diet, since you can get plenty of the same benefits from alcohol-free choices such as coffee, tea, grapes, and berries.