Touro study: Effects of high fructose diets can be reversed in days

Dr. Jean-Marc Schwarz of Touro led this pilot study on fructose in conjunction with the University of California, San Francisco. The diets of eight healthy men between the ages of 18 and 64 were closely monitored for nine days as they were given a high-fructose diet. The same subjects were then monitored for another nine days, this time with a diet in which complex carbohydrates replaced fructose (while maintaining the same number of calories). The effects of the food from both diets were studied.

“We can really see the results of the consequence of the (high-fructose) diet,” Schwarz said of the study. “You increase liver fat and you increase the fat in the blood after the high fructose diet. If you go from the high fructose diet to the low fructose diet, then you decrease, basically the fat in the blood and you decrease the fat in the liver in a significant way.”

What Schwarz found surprising was that the subjects all reacted to the diet in the same way: Once taken off the high-fructose diet, the fat in the blood and liver decreased within days.

“All of them had the same kind of response,” Schwarz said. “(The subjects) all increased the conversion of sugar to fat with the high-fructose. They all basically increased the blood lipids and they all increased the liver fat (with the high fructose diet). When we did the other sequence (with complex carbohydrates), they all decreased the conversion: Basically all the subjects had the same chart.”

What does this mean for the average person? Schwarz believed that the study is indicative of the positive effects of limiting fructose in your diet and that results will show.

“It really suggests that if you restrict your fructose intake — if you don’t drink soda, if you don’t eat processed foods that have a lot of fructose — even if you keep your carbohydrates as 50 percent of your energy intake, you still you have a very quick beneficial effect.

“When you drink (sodas and juices) it’s more likely to create those problems,” Schwarz added. “If you have fruit for example, fruit will contain fructose as well, but because it comes in its natural packaging, you have fiber and you have things that delay the absorption and avoid the tsunami effect of when you have a soda or juice."

Schwarz likened fructose to a “big wave of sugar” that feeds the liver and allows it to convert the sugar to fat.

“The message is to stay away from sugar and processed sugar, processed food and drinks and juice that contain a lot of fructose,” Schwarz concluded. “When it’s a drink, it’s quickly absorbed, so you want to stay away from that.”

Schwarz will next study the affect of high fructose diets on obese children who are known to be avid consumers of soda.

The study will focus on African-American and Latino children.

Contact Dianne de Guzman at 707-553-6833.