Fructose intake is higher than ever before, and it parallels an increase in obesity worldwide. The introduction of high fructose corn syrup (HFCS), about 20 years ago, correlates with a sharp spike in obesity that shows no signs of levelling off. A paper being presented at the American Society of Nephrology's 42nd Annual Meeting and Scientific Exposition in San Diego, California, will report that diets high in fructose increase the risk of developing hypertension.
Diana Jalal, MD (University of Colorado Denver Health Sciences Center), and her colleagues conducted the research. They calculated fructose intake in over 4500 adults without hypertension, based on dietary questionnaires. Consumption of fruit juices, soft drinks, baked goods, and candy was included in the questionnaire. The results showed that people who consume 74 or more grams per day of fructose (2.5 soft drinks per day) had a higher risk of high blood pressure. Specifically, people who consumed this level of fructose had blood pressure readings from 28-87% higher than those who did not consume as much fructose.
"These results indicate that high fructose intake in the form of added sugars is significantly and independently associated with higher blood pressure levels in the US adult population with no previous history of hypertension," the authors concluded.
Another study, presented at the American Heart Association's 63rd High Blood Pressure Research Conference in September, reported that a high fructose diet increases blood pressure in men. In that study, excessive consumption of fructose seemed to encourage the development of metabolic syndrome. Metabolic syndrome is a set of risk factors associated with heart disease and type II diabetes, and is defined as having three or more of the following risk factors:
- Increased waist circumference;
- High triglyceride levels;
- Low levels of high-density lipoprotein (HDL), a component of total cholesterol thought to have a protective effect;
- High blood pressure; and
- High fasting blood sugar.
Just two weeks on a diet of 50-70 grams of fructose per day experienced significant increases in blood pressure. The incidence of metabolic syndrome also nearly doubled in these men.
The researchers note that fruit, which contains 4 to 10g of fructose, also has many beneficial components such as antioxidants, vitamin C, and fibre, all of which counteract the effects of fructose alone. The processed variety of fructose, HFCS, does not contain these beneficial substances.
What is still not known is whether diets low in fructose can reverse high blood pressure or prevent its development. However, cutting back on processed foods and beverages containing high fructose corn syrup is a relatively simple step to improve your overall nutrition and reduce your risk of high blood pressure.
