Diet has a powerful impact on health. While no single food can significantly lower blood pressure, a well-balanced diet can do so. Since the 1990s, the Dietary Approaches to Stop Hypertension (DASH) diet has been proven to help control blood pressure. This diet emphasizes vegetables, fruits, whole grains, low-fat or fat-free dairy products, fish, poultry, beans, nuts, and vegetable oils. It also recommends eating lean cuts of meat, avoiding sugary drinks and sweets, and limiting sodium intake. Following this diet alone, without medication, can reduce blood pressure by 6 to 11 mm Hg in individuals with hypertension and by 2 to 3 mm Hg in those with normal blood pressure.

The effectiveness of this diet was scientifically proven in 1992 in a study sponsored by the U.S. National Institutes of Health. If people with high blood pressure following the DASH diet, it can help them reduce or even eliminate the need for blood pressure medication.

Diet can also play a role in preventing dementia. In 2015, American nutritional epidemiologist Dr. Martha Claire Morris published a study demonstrating that the MIND diet can slow cognitive decline with age. The MIND diet combines elements of the Mediterranean diet, known for its cardiovascular benefits, and emphasizes consuming vegetables and berries. It recommends eating at least six servings of leafy greens and at least two servings of berries per week, highlighting the association between higher intake of leafy greens, berries, nuts, and whole grains with better brain health. Several studies have since shown that people who follow the MIND diet experience slower cognitive decline, reduced risk of dementia, and fewer signs of Alzheimer's disease post-mortem. Although the exact cause-and-effect relationship is not fully understood, the results are promising.

Your diet can benefit both your health and the environment. In 2019, EAT, a nonprofit foundation that collaborates with scientists from 16 countries, alongside the medical journal, The Lancet, proposed the Planetary Health Diet. This diet emphasizes increasing plant-based foods while reducing meat and dairy consumption. A study published in the June 2024 issue of the American Journal of Clinical Nutrition found that those who closely followed this diet had a 30 percent lower risk of premature death compared to those who followed it the least. Additionally, there were reductions in disease-specific mortality: a 10 percent lower risk of death from cancer, a 14 percent lower risk of cardiovascular disease, a 47 percent lower risk of lung disease, and a 28 percent lower risk of Alzheimer's disease.

The Planetary Health Diet aims to nourish the global population, projected to reach 10 billion by 2050 while protecting the environment. Adopting this diet would lead to a 29 percent reduction in greenhouse gas emissions, a 51 percent decrease in agricultural land use, and a 21 percent reduction in fertilizer use. The diet is flexible, allowing substitutions such as tofu for lentils or perilla oil for olive oil. The key focus is on the overall diet, rather than any single food item.

Jeong Jae-hoon is a food writer and pharmacist. He covers a variety of subjects, including trends in food, wellness and medications. This column was originally published in Korean in Joongang Ilbo on June 20, 2024. – Ed.