From the article:
The study shows that the risk of dying prematurely from all causes was reduced by almost a third, and the risk of cardiovascular disease by about a quarter in people who ate 800 grams of fruit and vegetables every day, compared with those who ate very little or no fruits and vegetables.
This study was a meta-analysis of 142 articles from 95 population studies and found the risk of heart disease, stroke, and premature death decreased by 10.8% for each 200-gram (2 servings) increase in consumption of fruit or vegetables.
Most of the 95 studies adjusted the data for other health factors including physical activity, smoking, excessive drinking, eating processed meat.