Healthy diet

A healthy diet is a way of eating that maintains or improves overall health. It provides the body with essential nutrition to function properly. This includes water and macronutrients, which are protein, fats, and carbohydrates. It also includes micronutrients, which are vitamins and minerals. A healthy diet provides adequate fiber and food energy. Most experts suggest focusing on fruits, vegetables, and whole grains.

Many healthy diets include little to no ultra-processed foods. They also limit sweetened beverages to maintain wellness.

To understand how a healthy diet works, we can look at four core principles. The Food and Agriculture Organization and the World Health Organization (WHO) established these rules. First, a diet must be adequate. This means it meets the body's energy and nutrient requirements without exceeding them. Second, a diet must be diverse. This involves including various nutritious foods across different food groups to secure all necessary nutrients. Third, a diet must be balanced. It should include protein, fats, and carbohydrates in a way that supports growth and prevents disease. Finally, a diet should be moderate. This means eating only small amounts, or none at all, of foods like highly salty or sugary items.

Different organizations offer specific dietary patterns to help people eat well. The United States Department of Agriculture (USDA) suggests three patterns for a 2,000 kcal diet. The first is the Healthy U.S.-style Pattern. The second is the Healthy Vegetarian Pattern. The third is the Healthy Mediterranean-style Pattern. These patterns emphasize health and environmental sustainability. They suggest that diets higher in plant-based foods, like legumes and nuts, have less environmental impact.

The USDA guidelines help groups develop recipes and meal plans.

Specific nutritional recommendations help prevent disease and maintain weight. The WHO recommends eating at least 400 grams of fruits and vegetables every day. This measurement does not include starchy roots like potatoes or cassava. The WHO also suggests limiting fats to no more than 30% of total calories. It is better to choose unsaturated fats over saturated fats and to avoid trans fats entirely. For salt, consuming less than 5 grams per day can reduce cardiovascular disease risk. Additionally, limiting simple sugars to less than 10% of caloric intake is advised. Some experts suggest even lower levels, such as 5% or 25 grams, might be better.

Access to healthy food is a major global challenge. While the number of people unable to afford a healthy diet fell from 2.76 billion in 2019 to 2.60 billion in 2024, many regions struggle. In Africa, the number of people unable to afford a healthy diet rose from 864 million to over 1 billion. In low-income countries, this number grew from 464 million in 2019 to 545 million in 2024. This represents 72% of the population in those areas. In lower-middle-income countries, excluding India, the number rose from 791 million to 869 million. These statistics show that food affordability is often a political issue.

There are many surprising facts about how specific foods affect our bodies. The American Heart Association and other groups note that eating colorful vegetables provides protection. For example, tomatoes cooked with oil and cruciferous vegetables like cauliflower may help protect against cancer. Allium vegetables, such as garlic, are also mentioned for their benefits. Research shows that insufficient fruit and vegetable intake causes 2.8% of deaths worldwide. Furthermore, the type of carbohydrate matters more than the total amount. Choosing whole grains and beans is better than consuming highly processed, sugary drinks.

Understanding nutrition connects our daily choices to broader biological and social systems. Nutrition facts labels are mandatory in some countries to help consumers make informed choices. This allows people to compare the components of different foods. Experts like Marion Nestle note that while advice seems to change, the basic ideas remain the same. These include eating less, moving more, and eating plenty of fruits and vegetables. By focusing on minimally processed foods, we can promote health and prevent chronic diseases. This includes reducing the risk of diabetes, stroke, and heart disease.