The China Study: monumental research, groundbreaking results
The China Study is a monumental look at 6,500 adults across 65 counties of China. It analysed the blood, urine, diet and food intake of these people. China was chosen because 87 per cent of the population is from the same ethnic group, the Han people, and were from rural and semi-rural China where they had lived and eaten food from the same area most of their lives. This massively limited the chance of differences in disease susceptibility being due to genetics and concentrated on the impact of diet and lifestyle on disease. Nutrient levels varied considerably from county to county and two distinct groups of diseases emerged: diseases of affluence and diseases of poverty. There were marked patterns between each group. For example, a region that had high rates of breast cancer also had high rates of heart disease but not pneumonia. In rural China, affluent people tended to suffer from certain cancers, along with diabetes and heart disease. People with low nutrition bore other diseases such as pneumonia, peptic ulcers and parasitic diseases but not cancer or heart disease. You might conclude that’s because poor people die young, before they develop ‘Western’ diseases but not so, say the scientists in The China Study. All results were ‘age-standardised’ (age was taken into account) so the result was clear – people with a low intake of nutrients were getting less, or no, ‘Western’ diseases. The next important question was, which nutrients, when eaten in higher levels, were causing ‘Western’ diseases?