A study that culls health data for 1.8 million people over more than 57 years of research finds that controlling high blood pressure, cholesterol and glucose could halve the number of heart attacks attributable to being overweight or obese and pare the number of strokes linked to excess weight by 75 percent.

In populations in which being overweight or obese are widespread, the new research offers a guide to which public health policies most effectively drive down heart attacks and strokes. Published online in the Lancet on Thursday, the study was conducted by an international consortium of researchers led by Harvard University’s School of Public Health.

By far, the most effective of the available interventions, the study found, is treatment of hypertension. If all cases of high blood pressure stemming from being overweight or obese were kept in check by measures such as increased physical activity, medication and dietary sodium reduction, 31 percent of coronary heart disease cases caused by excess weight could be averted, the authors reckoned. Eliminating hypertension could drive down the incidence of strokes linked to excess weight by 65 percent.

Controlling glucose was found to be the next most effective means of reducing heart disease and strokes attributable to excess weight, followed by reducing serum cholesterol.

In this massive collection of studies, being overweight was associated with a 26 percent increased risk of heart attack and a 13 percent increased risk of stroke. (This finding appeared to contradict studies suggesting that those with a body mass index between 25 and 30 bear no greater risk of heart attack or stroke than those with BMIs bellow 25.) On average, getting treatment for hypertension, high cholesterol and high glucose readings reduced an overweight person’s increased likelihood of suffering a heart attack to 13 percent on average, and brought her risk of stroke down to that of a person of normal weight.