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| Sarah Kimmins |
Mothers get all the attention. But a study led by McGill researcher Sarah Kimmins suggests that the father’s diet before conception may play an equally important role in the health of their offspring. It also raises concerns about the long-term effects of current Western diets and of food insecurity. THE research focused on vitamin B9, also called folate, which is found in a range of green leafy vegetables, cereals, fruit and meats. It is well known that in order to prevent miscarriages and birth defects mothers need to get adequate amounts of folate in their diet. But the way that a father’s diet can influence the health and development of their offspring has received almost no attention. Now research from the Kimmins group shows for the first time that the father’s folate levels may be just as important to the development and health of their offspring as are those of the mother. Indeed, the study suggests that fathers should pay as much attention to their lifestyle and diet before they set out to conceive a child as mothers do. “Despite the fact that folic acid is now added to a variety of foods, fathers who are eating high-fat, fast food diets or who are obese may not be able to use or metabolize folate in the same way as those with adequate levels of the vitamin,” says Kimmins. “People who live in the Canadian North or in other parts of the world where there is food insecurity may also be particularly at risk for folate deficiency. And we now know that this information will be passed on from the father to the embryo with consequences that may be quite serious.” The researchers arrived at this conclusion by working with mice, and comparing the offspring of fathers with insufficient folate in their diets with the offspring of fathers whose diets contained sufficient levels of the vitamin. They found that paternal folate deficiency was associated with an increase in birth defects of various kinds in the offspring, compared to the offspring of mice whose fathers were fed a diet with sufficient folate. “We were very surprised to see that there was an almost 30 per cent increase in birth defects in the litters sired by fathers whose levels of folates were insufficient,” said Dr. Romain Lambrot, of McGill’s Dept. of Animal Science, one of the researchers who worked on the study. “We saw some pretty severe skeletal abnormalities that included both cranio-facial and spinal deformities.” The research from the Kimmins’ group shows that there are regions of the sperm epigenome that are sensitive to life experience and particularly to diet. And that this information is in turn transferred to a so-called epigenomic map that influences development and may also influence metabolism and disease in the offspring in the long-term. (The epigenome is like a switch, which is affected by environmental cues, and is involved in many diseases including cancer and diabetes. The epigenome influences the way that genes are turned on or off, and hence how heritable information gets passed along). Although it has been known for some time that there is a massive erasure and re-establishment that takes place in the epigenome as the sperm develops, this study now shows that along with the developmental map, the sperm also carries a memory of the father’s environment and possibly even of his diet and lifestyle choices. “Our research suggests that fathers need to think about what they put in their mouths, what they smoke and what they drink and remember they are caretakers of generations to come,” said Kimmins. “If all goes as we hope, our next step will be to work with collaborators at a fertility clinic so that we can start assessing the links in men between diet, being overweight and how this information relates to the health of their children.” An important factor that cannot, however, be overlooked in the campaign for health food is economic factor, especially for blacks around the world. Results of a recent study shed new light on factors underlying well-known and well-documented health disparities across racial and ethnic groups. According to lead researcher and Johns Hopkins University School of Nursing assistant professor Kelly M. Bower, PhD, MSN/MPH, RN, and colleagues from the Bloomberg School of Public Health, findings suggest that, when compared with other neighborhoods and without regard to income, predominantly black neighborhoods have the most limited access to supermarkets and to the healthier foods such markets sell. The study explored food store availability in over 65,000 rural and urban census tracts across the country, comparing the numbers of supermarkets with more than 50 employees, grocery stores, and convenience stores in communities with varied economic and racial compositions. The researchers found that the more impoverished a neighborhood, the fewer the number of independent or chain supermarkets and the less access to fresh fruits, vegetables, low-fat milk, high-fiber foods, and other healthy meal and snack options. The same finding holds true for all predominantly black neighborhoods — whatever the economic status — when compared with predominantly white or Hispanic communities. The researchers noted that education about positive food choices, while important, is likely of limited help when people lack access to supermarkets and other sources of healthy foods. Local interventions based on knowledge of the local food environment are most likely to be successful. They note that there are local initiatives around the country currently working to promote access to health food options but that they need to be evaluated so we can better understand their successes and challenges. Food access initiatives include mobile grocery stores, ordering foods from supermarkets online for delivery with food stamps, and tax incentives for supermarkets to locate in low-income minority communities. “Race, ethnicity, income, and geography all play a role in access to quality foods and the opportunity to make healthy choices,” Bower says. “To address health disparities, we need to understand and alter the factors that contribute to them. The availability of high-quality, healthy food could be one of those factors that is within our power to alter.”
