A high-quality diet reduces the risk of cardiovascular disease in humans.

Study: Changes in diet and physical activity resulting from the Strong Hearts, Healthy Communities randomized cardiovascular disease risk reduction multilevel intervention trial

The study helped women eat more fruits and vegetables, which are known to be good for the heart, and that supports the idea that eating better can lower heart disease risk.

Study: Association between Life's essential 8 and incident cardiovascular disease among individuals with depression: a prospective study.

This study found that people with depression who followed a healthy lifestyle — including eating well — had much lower rates of heart disease. Even though they looked at many healthy habits together, eating a good diet was part of what made the difference.

Study: Development of a diet pattern assessment tool for coronary heart disease risk reduction

This study found that people who ate healthier, more balanced meals had lower levels of body fat and inflammation — both signs of lower heart disease risk — so yes, eating better helps protect your heart.

Study: Cardiovascular Disease Prevention by Diet Modification: JACC Health Promotion Series.

This study says eating more fruits, veggies, whole grains, and healthy proteins — and less junk food — helps prevent heart disease, which is exactly what the claim says.