Sun Z.S. Empie W.M. 2012, ‘Fructose Metabolism in Humans.’
Accessed on 10th April 2012. http://www.medscape.com/viewarticle/777692_1
Fruits and vegetables are good for you is what we constantly hear! Currently, there are studies being done on the consumption of fructose and its relation to public health. Fructose is found in most fruits and vegetables but a higher percentage in fruits! Fresh fruits are always good and refreshing! There’s nothing better than a cold piece of watermelon on a sunny day or a ‘bess’ pineapple chow on the beach. Although fructose occurs naturally, other sugars such as beet is produced industrially so there’s added sugars to our diet. Over the past few years, there has been an increase in metabolic syndrome and well to no surprise, obesity worldwide. Most of these health disorders are related to sugar intake. Also, the fructose moiety in sugars was hypothesized to be a cause of high serum uric acid which could lead to Type-2 diabetes. Another hypothesis stated that dietary fructose may cause Non Alcoholic Fatty Liver Disease (NAFLD) and augmented de-novo triglyceride synthesis, based on an analysis of hormone regulated lipid pathways in the liver. High levels of fructose on our diets increase serum triglycerides.
The metabolic fate of fructose was reviewed by doing isotope trace studies in humans. The first test was done on persons that do not exercise for 3-6 hours. The 2nd test was done on persons that exercise for 2-3 hours. The mean oxidation rate of dietary fructose was 45.0% ± 10.7 for those that didn’t do exercise and 45.8% ± 7.3 in persons that exercised. A test was also done for the consumption of both fructose and glucose. When fructose was ingested with glucose, the mean oxidation rate of the mixed sugars increased to 66.0% ± 8.2 for persons that exercise. The mean conversion rate from fructose to glucose was 41% ± 10.5 in 3–6 hours after intake. It was found that less than 1% of the ingested fructose is directly converted to plasma TG. Approximately a quarter of the ingested fructose can be converted to lactate just within a short period. This increases the blood lactate concentration. We all know the story about Mr. lactate don’t we? Additionally, at short periods, a minimum amount of fructose carbons enter the pathway of liponeogenesis after fructose intake.
The study was not a full representation of real life diets and the data was limited. However, the paper did give a general idea of how fructose is utilized in the body. The focus was mainly between individuals that exercise and individuals that don’t.