8 Things the Healthiest Diets Have in Common

By R.Davies, PhD・Diet Atlas
Published June 23, 2026 | 5 min read

Key Takeaways
We reviewed eight of the world's healthiest diets to identify eight of the healthiest features that they all have in common. All the diets are plant-based, have pretty much a balanced macronutrient profile, favour whole grains over refined ones, regularly eat legumes and oily fish. They cut out ultra-processed foods, limit red meat and keep the rules and recommendations flexible.

Key Takeaways

We reviewed eight of the world's healthiest diets to identify eight of the healthiest features that they all have in common.

All the diets are plant-based, have pretty much a balanced macronutrient profile, favour whole grains over refined ones, regularly eat legumes and oily fish.

They cut out ultra-processed foods, limit red meat and keep the rules and recommendations flexible.

We have reviewed over 30 diets, which include some of the world’s healthiest diets and eating patterns. These include the Mediterranean, DASH, TLC, Anti-inflammatory, Volumetrics, Blue Zone, Nordic and the MIND diets.

Looking at these diets next to each other, one thing becomes clear — they share more similarities than differences. In fact, they are all pretty much related to each other in one way or another; they’re really a family of diets, which all descend from the Mediterranean diet.

So it comes as no surprise that the same foods, patterns and eating habits turn up again and again. There are no brand names. No special products or gadgets required. There is no specific ratio of carbs or fat.

Taken collectively, there are dozens of studies showing that all these diets are safe, healthy, nutritious and can be followed easily by vast swaths of people. Here’s what they all have in common.

The foods that appear repeatedly, the habits that recur across every culture and continent, are the real story. Not the brand name. Not the specific ratio of carbs to fat. The patterns underneath.

1. Plants Front and Centre

All eight diets are built around plants, all of which fall under the plant-based diet umbrella. Vegetables, fruits, legumes, nuts, seeds, and whole grains make up the majority of calories in every single one of these diets.

This is no coincidence. Several independent studies have shown that the more plants you eat, the lower your chances of getting heart disease, type 2 diabetes, certain cancers and shorter life-expectancies.

The Blue Zone diet gets over 80% of its calories from plants. The Mediterranean and Anti-inflammatory diets are high in vegetables and olive oil. The MIND diet calls for at least six servings of leafy greens a week. The Nordic diet promotes eating berries, root vegetables, and whole grains.

Although all the diets are “plant-forward”, none of them recommend going fully vegan. However, let’s be clear, plants are the main event with everything else playing a supporting role.

2. Whole Grains are Preferred Over Refined Ones

None of the healthiest diets are “low-carb” or fear carbohydrates. In fact, in all of the diets, carbohydrates are the main macronutrient, making up anywhere from 40 to 60% of total calories.

Oats, brown rice, rye, barley, quinoa, and whole wheat — these feature in all of the diets. But what's absent is just as telling: white bread, refined cereals, and processed grain products are consistently cut back or completely absent.

Whole grains provide fibre, B vitamins, and magnesium, and release energy more slowly than their refined equivalents. This helps keep your blood sugar levels and hunger low and stable.

The TLC diet recommends at least six servings of whole grains daily. The DASH diet recommends six to eight. The Nordic diet promotes eating rye and oats. The logic is the same across all of them: unprocessed grains keep your gut and heart healthy.

3. Legumes a Staple, Not an Afterthought

Lentils, chickpeas, black beans, kidney beans, edamame — these appear consistently across all eight diets, and in some (e.g, Blue Zone and Mediterranean), they serve as the primary source of protein.

Legumes are high in protein and fibre and low in saturated fat. They are inexpensive and filling. They are linked to lower cholesterol, better blood sugar control, and reduced cardiovascular disease risk.

The MIND diet recommends beans at least four times a week. The DASH and TLC diets both include three to five servings a week. If there is a single food that consistently appears among the world’s healthiest diets, it is probably the humble bean.

4. Healthy Fats are Favoured Over Saturated Ones

None of the eight diets eliminates fat. In fact, several of them are relatively high-fat (around 25-40% total calories). However, what they share is a clear preference for unsaturated fats like olive oil, rapeseed oil, nuts, seeds, and oily fish, over saturated fats from butter, full-fat dairy, processed foods and fatty meats.

The Mediterranean diet is built around extra virgin olive oil. The Nordic diet uses rapeseed oil as its primary fat. The TLC diet emphasises replacing saturated fat with unsaturated fats. The DASH and MIND diets both include nuts and oily fish.

The consistent swap, from saturated to unsaturated fat, is shown to lower LDL cholesterol, inflammation and support cardiovascular health.

5. Eat Oily Fish Regularly

Salmon, mackerel, herring, sardines, trout — oily fish appear regularly across six of the eight diets, and are at least an encouraged choice in all of them. Oily fish are rich in omega-3 fatty acids (EPA and DHA), which are shown to lower blood triglycerides, blood pressure, inflammation and support brain health.

The Mediterranean diet recommends fish at least twice a week. The Nordic diet positions herring and salmon as the centrepieces of meals. The MIND diet includes at least one serving a week specifically for brain health. The DASH and TLC diets both recommend fish as a better protein option over red meat. As far as protein recommendations go, none of the diets gives a numbered target, but all advise eating oily fish at least twice a week.

6. Cut Out Ultra-Processed Foods

This is the point on which all eight diets are in agreement: ultra-processed foods have no place in a healthy diet. Crisps, ready meals, fast food, packaged biscuits, sugary cereals, processed meats, and fizzy drinks are either eliminated or significantly restricted across all of the diets.

The reasons are well known. Ultra-processed foods are usually high in added sugar, refined carbohydrates, unhealthy fats, and sodium, while being low in fibre, vitamins, and minerals. They are engineered to override your natural hunger cues, making it easy to overeat them without noticing. They are designed for over-consumption.

People in the Blue Zone regions consume almost no ultra-processed foods. The Volumetrics diet works by replacing calorie-dense processed foods with water-rich whole foods. The MIND, Anti-inflammatory, TLC, DASH, and Nordic diets all explicitly recommend cutting out processed food as a central goal.

7. Limit Red and Processed Meat

Red meat is part of all eight diets, but it is always eaten in the same way: occasionally, in small amounts, and secondary to fish, poultry, and plant proteins.

The Blue Zone diet treats meat as a rare treat — a few times a month at most. The Mediterranean follows a similar pattern, usually being “part” of a dish, just another ingredient and not the main part. The MIND diet recommends fewer than four servings of red meat a week. The Anti-inflammatory diet identifies processed meat as one of the most pro-inflammatory foods around, so it also limits it.

None of the diets explicitly bans red meat. But all of them clearly differentiate between the occasional lean red meat (acceptable) and daily intake of processed meats like sausages, bacon, and deli meats (avoid). That line is the same in every one of the diets.

8. Keep It Flexible — Not Rigid

One of the most underrated and overlooked things these diets share is what they do not do. They don’t ban entire food groups, have macronutrient targets, require precise calorie counting, clock-watching, or demand perfection at every meal.

Every one of the eight “diets” is really a pattern of eating rather than a strict set of rules. The Mediterranean diet allows wine in moderation and desserts on special occasions. The Blue Zone diet is built around cultural habits rather than macronutrient ratios. The Volumetrics diet just asks you to shift the balance of the foods on your plate and not eliminate anything outright. The MIND diet scores how often you eat the right foods — not whether every single meal is perfect.

What all of these diets realise is that what looks good on paper or a spreadsheet doesn’t necessarily work in the real-world; not in the long-run anyway. Flexibility matters because adherence matters. The best diet in the world is the one you can actually follow, long term. Rigid diets get abandoned. Sustainable eating “patterns” become a permanent lifestyle change.

Bottom Line

The fine details of each of these diets differ — olive oil versus rapeseed oil, salmon versus sardines, barley versus brown rice. But take a step back and look across all eight of these diets, and the same picture appears every time.

Eat more plants. Choose whole grains. Eat more legumes. Use healthy fats. Eat oily fish. Avoid ultra-processed foods. Go easy on red meat. And find a pattern you can actually stick to.

That is not a complicated formula. It is a practical one. If the world's healthiest eating patterns all agree on these points, that is probably worth paying attention to.

Frequently Asked Questions

What do the world's healthiest diets have in common?

The world's healthiest diets include the Mediterranean, DASH, Blue Zone, and MIND diets. They are all plant-forward diets, rich in whole grains, legumes, and healthy fats, and limit ultra-processed foods, added sugars, and red and processed meat.

Is there one single "best" diet for health?

No. There is no single perfect diet. However, the Mediterranean has the best evidence, and all eight diets reviewed here share the same core features. The best diet for you is the one that fits your health goals, lifestyle, and food preferences.

Do these diets have to be plant-based or vegan?

No. All eight diets include animal foods to different degrees — fish, eggs, poultry, and dairy all feature in all of them. However, all of the diets are “plant-based” meaning that the majority of the food in the diet comes from plants.

Are these diets good for weight loss?

Most of the diets are linked to healthy body weights and modest, sustainable weight loss. Some of them actually perform just as well as standard calorie-restriction diets that are designed for weight loss. These diets are generally better suited to long-term weight maintenance than rapid short-term results.

How do I choose the right diet for me?

It depends on your health goals, medical history, and lifestyle. Our Diet Atlas reviews and scores each of the eight diets in this article (and many others) to help you find the best fit, and what to avoid.