The study was published recently in the journal Food & Function. It was conducted by researchers associated with the University of São Paulo as well as employees of the Nestlé Group.
The researchers recruited 151 boys and girls ages 9 to 13 in the city of Ribeirão Preto. Of that group 141 met the inclusion criteria and the blood draw from one of those did not yield reliable data.
The children all had access to city water, sanitation, electricity, and internet through broadband connectivity. The municipal human development index (MHDP) was 0.8. MHDP is an assessment done by the United Nations Development Programme and includes measures of things like life expectancy and expected years of schooling. This would rank the areas where the children came from as more affluent than Brazil as a whole, which as a national HDI of .761, according to the UN.
The researchers noted that in Brazil as elsewhere in the developed world diets have shifted toward more processed food with fewer micronutrients and higher levels of saturated fat, sugar and sodium. The researchers were looking to see whether levels of the omega-3 fatty acids EPA and DHA, vitamin A (which they referred to as retinol), beta carotene (a vitamin A precursor) and riboflavin correlated to levels of DNA damage. The DNA damage was assessed with a single-cell gel electrophoresis technique, a so-called comet assay.
Omega-3s shown to preserve DNA; same not seen for vitamins
The researchers found higher levels of EPA and DHA were associated with lower levels of DNA damage. The researchers did not find the same inverse relationship with retinol, beta-carotene or riboflavin.
The research confirms earlier studies that have found higher levels of omega-3s have been associated with less DNA damage. Other studies that show this relationship included in vitro research with blood tissue and vascular endothelial cells and a study done in diabetic individuals. This apparently was the first such in vivo study to look at this relationship in otherwise healthy adolescents.
“The present study suggests that the implementation of public nutritional education policies to improve the nutritional status may help prevent the development of diseases related to a greater DNA damage,” the researchers concluded.
Result seen as having interesting healthy aging implications
Noted omega-3s expert William S. Harris, PhD, of the Sanford School of Medicine at the University of South Dakota, said the research is interesting on several levels. Harris is also a principal in the omega-3s testing firm OmegaQuant.
“I had never heard of this DNA assay before,” Harris said. He said the technique, in which broken fragments of DNA are induced to migrate away from their parent molecules on a slide, appears to be an elegant way to assess the integrity of the DNA structures.
And Harris said the study offers a cogent mechanism of action for some of the epidemiological effects of omega-3s that have been observed over the years.
“We know that people with higher levels of omega-3s just live longer,” Harris told NutraIngredients-USA. “The significance of this research is that higher levels of omega-3s are associated with a health protective mechanism that keeps DNA intact and operating properly.”
DNA degradation is one of the mechanisms of aging. As damage accumulates in the DNA strands, errors in replication accelerate and cells, and the tissues they make up, start to lose proper function. This mechanism of action figures into conditions such as cancer, neurological diseases and premature aging.
“Aging writ large is associated with DNA damage and this is one more mechanism by which omega-3s can contribute to healthy aging by slowing the rate of DNA damage,” Harris said.
Source: Food & Function
April 22, 2020 DOI: 10.1039/c9fo02551k
DNA damage is inversely associated to blood levels of DHA and EPA fatty acids in Brazilian children and adolescents
Authors: de Barros TT, et al.