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  • Yeast provides scientists with a cellular structure to test anti-aging substances and see their reaction at a cellular level.
  • Experts say short-term diets do not work as well as changing to healthy foods.
  • They say dietary changes rather than caloric restriction increase lifespan and improve aging health.

Dietary changes without caloric restriction help maintain youth in yeast cells, according to researchers in the Epigenetics Programme at Babraham Institute in Cambridge, United Kingdom.

In a study published today in the journal PLOS Biology, the scientists reported that an unrestricted galactose diet in budding yeast minimized cell changes during aging, irrespective of diet later in life.

They say their findings could help promote healthy aging in humans.

Galactose is a simple sugar that is transformed into glucose in the liver before it’s used as energy. It is generally abundant and normal in human diets.

Galactose comes from the breakdown of lactose, according to the International Dairy Federation. Therefore, the most common foods contributing to galactose production in the human diet are dairy products.

Other foods containing galactose include fruits, vegetables, nuts, grains, fresh meat, and eggs. However, these foods have only a small amount. The primary sources of galactose in the human diet are milk and yogurt.

The researchers found two separate aging trajectories in budding yeast. Changing the overall type of nutritional intake contributed to a healthier aging trajectory compared to yeast cells that were subject to intermittent dieting.

They suggest that moving toward a healthy aging trajectory may be possible based on the foods you eat. Healthy foods will transfer you to a healthier trajectory.

“It’s hard to make conclusive claims in humans from results studied in yeast,” said Caroline Thomason, RD, CDCES, a dietitian and diabetes educator based in Washington, D.C., who was not involved in the study.

“However, there is a growing body of research that shows that when we focus on higher-quality nutrition, both our health and weight can improve,” Thomason told Medical News Today. “While the focus is on, say, eating more fruits and vegetables, the indirect implication is that you’re taking in fewer calories than you were previously, and thus, weight loss naturally takes place, and health markers can improve.”

Budding yeast (saccharomyces cerevisiae) is a chemical and genetic screening platform, according to a report published in 2018 in FEMS Yeast Research.

“In yeast, many pathways that are relevant for aging and disease in humans are well conserved, including nutrient signaling, cell cycle regulation, DNA repair mechanisms, mitochondrial homeostasis, lipostasis, protein folding, and secretion, proteostasis, stress response, and regulated cell death,” according to the report.

The authors noted that yeast is a suitable cellular environment for identifying or mechanizing anti-aging substances.

In a 2014 study, researchers used yeast to test anti-aging substances. This study helped lead to the discovery of the natural polyamine spermidine as a potential anti-aging agent.

Weight loss typically involves caloric restriction, meaning you reduce how much you eat and how many calories you take daily.

The current study, using yeast, suggests that it is healthier and promotes a longer life to change what you eat rather than how much you eat.

The researchers say that counting calories is unnecessary and looking for healthy foods actually better promotes longevity.

“I always stress that short-term diets don’t work,” said Anne Danahy, a registered dietician who was not involved in the study.

“Good health is about long-term healthy habits (diet, exercise, sleep, stress management, etc.). In terms of your diet, it’s your overall eating pattern that counts — the foods you eat most of the time over weeks, months, and years,” Danahy told Medical News Today.

The authors noted that the study shows a transition to healthy aging is possible, at least for yeast. Substituting galactose as the primary caloric input is neither achievable nor valuable in humans.

Still, the findings suggest dietary change without restriction can offer a path to aging health benefits currently only observed under dietary restriction.

“The most important point here likely is that strictly focusing on a calorie deficit alone without attention to quality nutrition will likely make your life more challenging and harder to stick to the calorie restriction,” Thomason said. “When you focus on foods higher in quality that naturally help keep you full and allow you to increase the volume of food you’re eating for fewer total calories, eating sustainably becomes a whole lot easier.”

The National Institute on Aging defines calorie restriction as reducing your intake below what is typical without surprising yourself of essential nutrients.

These are not temporary weight loss plans but instead a way to change eating patterns permanently.

The authors of the study note that improved aging health is not achievable by reducing calories alone but rather by optimizing their diet.

The yeast experiments showed that changing your diet can change the trajectory from unhealthy to healthy aging.

“Most people know that eating a healthier diet will promote better health and quality of life as you age,” Danahy said. “It’s so much easier to eat well if you don’t have to break a lifetime of not-so-healthy habits. Children who grow up eating lots of fruits, vegetables, plant-based proteins, and a whole-food diet tend to continue those habits as adults. And research shows that people who eat better have a lower risk of most chronic diseases.”

“However, I always tell people it’s never too late. Even small changes later in life can improve your health and help you live longer,” Danahy added. “I’ve worked with many people who have normalized their blood pressure, lowered cholesterol, and reversed diabetes by changing their diet. Once they realize how much better they feel, the desire for sugary or highly processed foods tends to fade away, making healthy habits easier to maintain.”