Obesity increases the risk of developing high blood pressure and heart disease

True. The prevalence of high blood pressure (hypertension) among obese people is greater than in the population at large. Consuming more kilojoules than we actually need for our level of activity can increase blood pressure; consuming less can lower blood pressure. The extent of these effects varies from person to person. Both energy imbalance (either an excess or deficiency of kilojoules in relation to needs) and over-fatness, even when one is in energy balance (kilojoule intake and needs are equal), contribute to hypertension. Overeating may contribute to high blood pressure in other ways. For example, as food (energy) intake increases, it is likely that more salt (sodium) or alcohol will be consumed.

'Burning' excess kilojoules with increased exercise can improve blood pressure control. Obesity can increase the risk of coronary heart disease in several ways:

The distribution of body fat is also important. Fat around the abdomen increases the risk of heart disease, strokes, diabetes and total mortality more than fat around the hips. What can we do about it? In general, if we decrease our total body fat with exercise and diet, fat around our 'middle' will also decrease. Abdominal exercise may reduce abdominal fat, but this needs confirmation. People generally think alcohol contributes to abdominal fatness, but curiously this has not been the subject of scientific studies. If it does contribute, then this may account for some of the connections between alcohol, high blood pressure and stroke.

Having said all of this, the increased health risk associated with obesity appears to be less after the age of 50 than before it.