Introduction,
In the pursuit of a longer, healthier life, a new study suggests an unexpected tool: a vegan diet. Research reveals that after just eight weeks on a plant-based diet, participants showed reductions in their biological age, marked by enhanced heart, liver, and metabolic health. This discovery has sparked interest in the role diet may play in slowing the biological aging process.
The Science of Biological Aging
Biological age, distinct from chronological age, refers to the physiological state of tissues and organs rather than the years someone has lived. Factors like diet, exercise, and lifestyle influence this biological clock. While chronological age is set in stone, biological age can fluctuate based on environmental and behavioural influences.
The recent study published in BMC Medicine explores this concept. Researchers recruited 21 pairs of identical twins, each twin raised under similar environmental and genetic conditions. This allowed for a rare opportunity to isolate diet as the primary variable. One twin adhered to a vegan diet, while the other consumed a balanced omnivorous diet. After two months, the results showed that those on a vegan diet had achieved a modest reduction in biological age, suggesting improved bodily function and health.
How DNA Methylation Reveals Age
The reduction in biological age among the vegan group was measured by analysing DNA methylation, a biological process that marks genes with chemical changes, essentially controlling which genes are active or inactive. This process acts as a biological clock, with changes in methylation levels linked to aging. The vegan twins’ DNA samples, taken at the beginning, mid-point, and end of the study, showed significant shifts in methylation patterns, indicating a reduction in biological age.
The mechanisms behind these changes may relate to the diet’s effects on inflammation, cellular health, and metabolic function. Plant-based diets are rich in antioxidants, phytochemicals, and anti-inflammatory compounds, which could help slow cellular aging. However, while the findings suggest short-term benefits, it remains uncertain how sustainable these changes are or if they translate to a longer life.
The Role of Weight Loss in Biological Age
Participants on the vegan diet lost, on average, two kilograms more than their omnivorous counterparts over the eight weeks, partly due to the 200 fewer calories they consumed daily. This weight loss could account for part of the biological age reduction since calorie restriction and weight management have been associated with lower biological age in past research. The benefits of weight loss on cardiovascular health, liver function, and metabolic processes likely contributed to the vegan group’s overall improved biological markers.
Yet, weight loss alone doesn’t paint the full picture. Dr. Varun Dwaraka of TruDiagnostic and Dr. Christopher Gardner from Stanford University, both experts in epigenetics and nutrition, advise that while weight loss may impact biological age, a plant-based diet’s nutrient profile could also play a significant role.
Nutritional Concerns of a Long-Term Vegan Diet
While these short-term effects are promising, experts caution that a strict vegan diet could have drawbacks, especially over a long period. Nutritional deficiencies in vitamins D, B12, calcium, and omega-3 fatty acids are common in vegan diets. These nutrients are essential for bone health, muscle maintenance, and neurological function, especially for aging adults. Without them, vegans may experience muscle loss, lower bone density, and even cognitive issues later in life.
Professor Tom Sanders, emeritus of Nutrition and Dietetics at King’s College London, acknowledges that vegan diets can offer protective effects against certain health conditions, such as cardiovascular disease and type 2 diabetes, particularly in middle age. However, he points out that older adults following a vegan diet might face health challenges due to nutrient deficiencies that develop gradually.
“In younger people, a vegan diet can indeed promote health benefits like improved cardiovascular health and reduced diabetes risk,” he says. “But in older vegans, the absence of specific nutrients can lead to muscle atrophy, low bone density, and even neurological disorders.”
Practical Adjustments for a Healthier Vegan Lifestyle
For those interested in adopting a vegan diet to reduce biological age, nutrition experts emphasize that careful planning is crucial. Incorporating fortified foods and supplements can help fill nutritional gaps, particularly for B12, iron, calcium, and vitamin D. Emphasizing high-protein foods like legumes, nuts, seeds, and whole grains is also essential for maintaining muscle mass and bone density.
Dr. Duane Mellor, a spokesperson for the British Dietetic Association, points out that the vegan group in the study was encouraged to eat twice the number of vegetable portions compared to the omnivore group. They also ate more fruits, legumes, and nuts, potentially adding to the health benefits observed. This nutrient-dense approach, combined with the high fiber content of plant-based foods, may help balance blood sugar levels, reduce cholesterol, and improve gut health, all of which are linked to a lower biological age.
The Link Between Diet and Biological Age: Room for Further Research
While the study provides a glimpse into how a vegan diet may reduce biological age, it is not without limitations. The small sample size of 21 twin pairs limits the study’s statistical power, and the short eight-week duration raises questions about the sustainability of these changes. Dr. Dwaraka and Dr. Gardner, authors of the study, suggest that longer-term studies with larger, more diverse samples are needed to confirm the relationship between diet and biological age.
Other researchers echo this sentiment, noting that different genetic backgrounds, lifestyles, and baseline health conditions may influence the extent to which diet affects biological aging. The field of epigenetics, the study of how lifestyle influences gene expression, is still relatively young. The changes observed in this study are promising, but more comprehensive research is necessary to solidify these findings.
Looking Forward, Can Diet Actually Rewind Aging?
While there is no “magic bullet” for aging, the study adds to a growing body of evidence suggesting that what we eat could influence our biological clock. Plant-based diets are becoming increasingly popular for their purported health benefits, but the long-term implications remain under investigation. While veganism may not be suitable for everyone, particularly older adults or those with specific health conditions, integrating more plant-based foods into one’s diet could offer health benefits without the risks associated with strict veganism.
Ultimately, the study emphasizes the importance of balance and personalized nutrition. Individuals should consider their age, health status, and lifestyle needs when choosing a diet aimed at slowing biological aging. For now, though, it seems that adding more fruits, vegetables, and legumes to one’s plate may be a small but impactful step toward a healthier biological age.
References
- Horvath, S., et al. (2013). DNA methylation age of human tissues and cell types. Genome Biology, 14(10), R115.
- Gardner, C. D., et al. (2023). Diet and DNA methylation in aging. BMC Medicine.
- Sanders, T. A. B. (2019). Nutritional implications of vegan diets. Proceedings of the Nutrition Society, 78(2), 133-145.
- Mellor, D. D., et al. (2018). Plant-based diets and age-related health outcomes. Journal of Geriatric Cardiology, 15(6), 504-513.
- Dwaraka, V., et al. (2023). Epigenetics and dietary influence on aging. TruDiagnostic Research Publications.
- Willett, W., et al. (2019). Food in the Anthropocene: the EAT–Lancet Commission on healthy diets. The Lancet, 393(10170), 447-492.
- Merrow, M., et al. (2017). Circadian rhythms and health: The role of dietary patterns. Chronobiology International, 34(7), 935-943.
- Barnard, N. D., et al. (2014). Plant-based diets and cardiovascular health: Review and meta-analysis. Journal of Nutrition & Diabetes, 13(5), 377-383.
- Eshel, G., et al. (2014). Diet, lifestyle, and aging: Toward a holistic approach. Annual Review of Public Health, 35, 273-291.
- Leach, M., et al. (2020). Aging and nutrition: An overview. Ageing Research Reviews, 57, 100999.