How does what we eat affect our aging?

The results of the study underscore the importance of thinking about nutrition holistically.

According to recent research from the Butler Columbia Aging Center at Columbia University Mailman School of Public Health, the answer to a seemingly simple question – what impact does what we eat have on our aging – is inevitably complex.

While the majority of analyzes have focused on the effects of a single nutrient on a single outcome, a conventional, one-dimensional approach to understanding the effects of diet on health and aging no longer gives us the complete picture. A healthy diet should be thought about in terms of balancing sets of nutrients, rather than optimizing a set of nutrients one at a time. Until recently, little was understood about how the dietary variations that occur naturally in humans affect aging. The results were recently published in the journal BMC Biology.

“Our ability to understand the problem has been complicated by the fact that nutrition and the physiology of aging are very complex and multidimensional, involving a high number of functional interactions,” said Alan Cohen, Ph.D., associate professor of environmental health. science at Columbia Mailman School.

“This study, therefore, lends further support to the importance of looking beyond just one nutrient at a time, as the single answer to the age-old question of how to live a long and healthy life.”

Cohen also notes that the findings are consistent with other studies demonstrating the need for higher protein intake in older adults, particularly to counteract sarcopenia and decreased physical performance associated with aging.

Researchers have identified key patterns of particular nutrients related to minimal biological aging by using multidimensional modeling tools to study the impact of nutrient intake on physiological dysregulation in older adults.

“Our approach presents a roadmap for future studies to explore the full complexity of the nutritional aging landscape,” observed Cohen, who is also affiliated with the Butler Columbia Aging Center.

The researchers analyzed data from 1,560 older men and women, ages 67 to 84, randomly selected between November 2003 and June 2005 in the Montreal, Laval, or Sherbrooke areas of Quebec, Canada, who were re-screened annually for 3-year and four-year follow-ups to assess on a large scale how nutrient intake is associated with the aging process.

Aging and age-related loss of homeostasis (physiological dysregulation) were quantified through the integration of blood biomarkers. Diet effects used the Geometric Nutrition Framework, applied to macronutrients and 19 micronutrients/nutrient subclasses. The researchers fitted a series of eight models exploring different nutritional predictors and adjusted for income, education level, age, physical activity, number of comorbidities, gender and current smoking status.

Four major trends were observed:

• The optimal level of nutrient intake depended on the measure of aging used. High protein intake improved/decreased some aging parameters, while high carbohydrate levels improved/decreased others;
• There have been cases where intermediate nutrient levels have performed well for many outcomes (i.e. arguing against a simple more/less is better perspective);
• There is a wide tolerance for nutrient intake patterns that do not deviate too much from the norm (“homeostatic plateaus”).
• Optimal levels of one nutrient often depend on levels of another (eg vitamin E and vitamin C). Simpler analytical approaches are insufficient to capture such associations.

The research team also developed an interactive tool to allow users to explore how different combinations of micronutrients affect different aspects of aging.

The results of this study are consistent with previous experimental work in mice showing that high-protein diets can accelerate aging earlier in life, but are beneficial at older ages.

“These results are not experimental and will need to be validated in other contexts. Specific findings, such as the importance of the combination of vitamin E and vitamin C, may not be replicated in other studies. But the qualitative finding that there are no simple answers to optimal nutrition is likely to hold: it was evident in almost all of our analyses, from a wide variety of approaches, and is consistent with evolutionary principles and a lot of previous work,” Cohen said.

Reference: “Multidimensional associations between nutrient intake and healthy aging in humans” by Alistair M. Senior, Véronique Legault, Francis B. Lavoie, Nancy Presse, Pierrette Gaudreau, Valérie Turcot, David Raubenheimer, David G. Le Couteur, Stephen J. Simpson and Alan A. Cohen, 1 September 2022, BMC Biology.
DOI: 10.1186/s12915-022-01395-z

The study was funded by the Australian Research Council, the Canadian Institutes of Health Research, the Quebec Research Fund (FRQ) and the Quebec Research Network on Aging.