Recent studies have highlighted the detrimental effects to hundreds of genes following the consumption of fructose, a form of sugar that’s extremely common in the typical Western diet. These damaged genes can lead to the development of diseases such as diabetes, Alzheimer’s, metabolic dysregulation, and cardiovascular disease.
These rat studies focused primarily on the hypothalamic and hippocampal regions of the brain, which regulate metabolic activity. Scientists at UCLA noted these epigenetic changes begin with impaired DNA methylation, so those with MTHFR gene variants may be particularly susceptible to this damage. They analyzed more than 20,000 genes in these rats, and drew their conclusions from the majority of over 900 of the genes that correlated strongly to the same metabolic activity in humans.
The young male rats in this study were fed either a diet high in fructose, a diet high in fructose supplemented with an Omega-3 oil supplement rich in DHA (Docosahexaenoic acid), or a standard diet that did not include fructose or DHA. At the end of the six week study, the rats who were fed the high fructose diet had elevated serum glucose, triglycerides, and insulin, and displayed impaired memory as tested by a maze they ran at the beginning and end of the study. Those fed high fructose with supplemented DHA had improved markers, including lower insulin and triglycerides, improved insulin resistance, and better memory. The group fed high fructose with DHA had results that were statistically similar to the control group, indicating that the DHA counteracted the effects of the fructose.
Researchers found that two specific genes, Bgn and Fmod, were significantly damaged by the excess fructose. The damage to these genes then sets off further damaging processes, all of which were improved with DHA consumption.
The senior author of the study, Xia Yang, commented on the remarkable nature of how DHA interacts with epigenetic markers, essentially resetting the entire gene pattern back to its original, undamaged state. The human body and brain are not equipped to produce DHA endogenously, so this nutrient must be acquired wholly from foods and supplementation. It’s essential in human physiological function for efficient and accurate memory formation and learning, and deficiencies have also been correlated with mental illness, cardiovascular disease, and some cancers.
This new information can help us modify our clients’ food plans, especially if they currently have, or have had in the past, significant fructose consumption. Reduction in the amount of fructose consumed is ideal, alongside the addition of foods that contain high amounts of DHA. The most absorbable dietary forms of DHA can be found in wild fish such as salmon, while the most effective supplementation would be cod liver oil, krill oil, and algae such as spirulina and chlorella, where DHA is produced in great quantity, and is the source of the DHA found in other sea life.
Vegetarians and vegans are more strongly at risk for the epigenetic damage from excess fructose consumption, as they have a higher fructose intake from fruits and decreased intake of fish. Supplementation with flax seeds can provide some benefit, though the types of omega-3s they contain are poorly converted to the needed DHA. Algae would remain a positive addition for them, as well, as it is plant-based and highly ecologically sustainable.