Recent research from the Harvard T.H. Chan School of Public Health offers a fascinating perspective on the role of macronutrients in our diet. Specifically, the study highlights that a higher intake of protein, as a percentage of total energy consumption, has beneficial effects on health, particularly in reducing the risk of cardiovascular disease. This raises important questions about the optimal balance between protein and carbohydrates in our diets. Should we rely less on carbohydrates as a primary energy source and consume more protein? And what does this mean for future dietary guidelines?

The Harvard Study: More Protein, Fewer Cardiovascular Risks

The Harvard study found that individuals who derive 21% of their total energy from protein have a 28% lower risk of cardiovascular disease and a 36% lower risk of coronary heart disease compared to those consuming only 16% of their energy from protein. Moreover, the study emphasizes that these health benefits are even more pronounced when red and processed meats are replaced with plant-based protein sources, such as nuts and legumes.

This suggests that a shift toward a diet higher in protein—and potentially lower in carbohydrates—could be key to improved cardiovascular health.

The Traditional Focus on Carbohydrates

The typical Western diet derives a significant portion of its energy from carbohydrates, primarily in the form of bread, pasta, rice, and processed foods. While carbohydrates are an important source of quick energy and have played a central role in traditional dietary patterns, the quality of these carbohydrates matters greatly.

Foods high in refined carbohydrates, such as white rice, sugar, and processed grains, are associated with spikes in blood sugar, insulin resistance, and an increased risk of metabolic syndrome. While complex carbohydrates like whole grains and vegetables provide a more stable impact on blood sugar levels, recent studies, including the Harvard research, question whether a high dependence on carbohydrates as a primary energy source is ideal.

The Benefits of Increasing Protein Intake

Proteins offer unique advantages for health. They have a higher thermogenic effect, meaning the body expends more energy to digest them, which supports stable blood sugar levels and can aid in weight management. Additionally, protein-rich diets contribute to a prolonged feeling of fullness, which may reduce overall calorie intake.

Proteins also help preserve muscle mass, particularly during weight loss, which is critical for maintaining a healthy metabolism and reducing the risk of metabolic diseases. Plant-based proteins, such as those found in nuts, legumes, and seeds, further enhance cardiovascular health. These sources not only provide protein but also include fiber, antioxidants, and healthy fats that positively impact blood pressure, cholesterol levels, and inflammation.

How Much Protein Is Optimal?

Current Dutch dietary guidelines recommend that 10-25% of total energy intake come from protein. However, the Harvard study suggests that increasing protein intake to 21% or more can yield significant health benefits. This requires a shift in focus: less reliance on carbohydrates as the primary energy source and greater emphasis on the quality and source of proteins.

For the average adult, this doesn’t mean simply eating more meat or dairy. Instead, it emphasizes incorporating more plant-based protein sources, such as legumes, nuts, and tofu, while reducing consumption of processed and red meats. Such changes could significantly amplify the health benefits associated with a higher-protein diet.

What Does This Mean for Future Dietary Guidelines?

Looking ahead to the Richtlijnen Goede Voeding 2025 (Dutch Dietary Guidelines 2025), the role of protein could become increasingly prominent. A shift toward a “#softpaleo”-style dietary pattern—characterized by reduced consumption of bread, pasta, and rice, and greater emphasis on vegetables, fruits, legumes, nuts, and moderate amounts of animal proteins—seems likely. This aligns with scientific evidence suggesting that a diet higher in plant-based protein and lower in refined carbohydrates is not only healthier but also more sustainable.

Moreover, recommending a higher protein intake as a percentage of total energy could become a new standard, paired with clear guidelines on the quality of protein and the importance of avoiding excessive intake of processed carbohydrates.

Conclusion: More Protein, Fewer Carbohydrates, Better Health

The findings of the Harvard study underscore the benefits of a diet that derives more energy from protein, particularly from plant-based sources. Increasing protein intake to 21% of total energy could provide substantial health benefits, especially in reducing the risk of cardiovascular disease.

For policymakers and nutritionists, this calls for a reevaluation of current dietary guidelines, with greater emphasis on the quality of macronutrients and the promotion of a protein-rich diet. For individuals, the message is simple: eat more vegetables, legumes, nuts, and moderate amounts of meat and dairy, while reducing processed carbohydrates.

The science is clear; now it’s up to us to adapt our plates accordingly.