Scientists now have a clearer picture of what kind of longevity diet can offer the best chance for a longer and healthier life.

Examining a range of longevity diet research from studies in laboratory animals to epidemiological research in human populations can allow scientists to gain a clearer picture of what sort of nutrition offers the best chance of a longer, healthier life, says USC Leonard Davis School of Gerontology Professor Valter Longo.

Longevity.Technology: Diet and exercise are the twin pillars of a healthy existence, but exactly what sort of food should we be consuming? And how much? And when? Even a cursory Google will transport you down a rabbit-hole crammed with fasting regimens, colour rules and diktats about chewing speed and rhythm. Of course, science has your back, and Dr Valter Longo, founder of the fasting mimicking diet, and co-author Rozalyn Anderson of the University of Wisconsin have published an article that overviews research to describe the longevity diet.

Publishing in Cell, Longo and Anderson explain the longevity diet is a multi-pillar approach based on studies of various aspects of diet, from food composition and calorie intake to the length and frequency of fasting periods [1].

“We explored the link between nutrients, fasting, genes, and longevity in short-lived species, and connected these links to clinical and epidemiological studies in primates and humans, including centenarians,” Longo said. “By adopting a multi-system and multi-pillar approach based on over a century of research, we can begin to define a longevity diet that represents a solid foundation for nutritional recommendation and for future research [2].”

Eating for longevity – what, when and how much?

Anderson and Longo reviewed hundreds of studies on nutrition, diseases and longevity, both in laboratory animals and humans; these were then combined with the authors’ own studies on nutrients and aging. Popular diets were analysed, including calorie restriction, the high-fat and low-carbohydrate ketogenic diet and the Mediterranean diet and other eating practices such as veganism and vegetarianism were also included.

Fasting is gaining in popularity, both for weight loss and health improvement. The article considers different forms of fasting, including intermittent, periodic and prolonged fasting. In addition to examining lifespan data from epidemiological studies, the team linked these studies to specific dietary factors affecting several longevity-regulating genetic pathways shared by animals and humans that also affect markers for disease risk. These include levels of insulin, C-reactive protein, insulin-like growth factor 1 and cholesterol.

According to Longo and Anderson, key characteristics of the optimal diet appear to be:

• Moderate to high carbohydrate intake from non-refined sources
• Low but sufficient protein from largely plant-based sources
• Enough plant-based fats to provide about 30% of energy needs.

Ideally, the day’s meals would all occur within a window of 11-12 hours, allowing for a daily period of fasting. Additionally, a 5-day cycle of a fasting or fasting-mimicking diet every 3-4 months may also help reduce insulin resistance, blood pressure and other risk factors for individuals with increased disease risks.

So, what does the longevity diet actually look like? Longo describes it as: “Lots of legumes, whole grains, and vegetables; some fish; no red meat or processed meat and very low white meat; low sugar and refined grains; good levels of nuts and olive oil, and some dark chocolate [2].”

Researching the longevity diet

In order to understand more about the effects of the longevity diet, a 500-person study is planned which will happen in southern Italy, an ideal location given that the longevity diet bears both similarities to and differences from the Mediterranean-style diets often seen in the so-called “Blue Zones”. These include Okinawa in Japan, Loma Linda in California, US and Sardinia in Italy. These communities have a high number of people aged 100 or older, and the diets in the area are typically plant-based or pescatarian and are relatively low in protein.

According to Longo, the longevity diet represents an evolution of these “centenarian diets” and features recommendations for limiting food consumption to 12 hours per day and having several short fasting periods every year.

In addition to the general characteristics, the longevity diet should be adapted to individuals based on sex, age, health status and genetics, the authors note. For instance, people over age 65 may need to increase protein in order to counter frailty and loss of lean body mass. Longo’s own studies have illustrated that higher protein amounts were better for people over 65 but not optimal for those under 65.

When it comes to optimising your diet for longevity, Longo says that it is important to work with a healthcare provider which is specialised in nutrition. Personalising a plan that focuses on smaller, discrete changes that can be adopted for life, rather than swingeing changes that could have harmful consequences and are difficult to maintain will be better in the long run. Causing a major loss of body fat and lean mass, followed by regaining the lost fat, can be harmful.

“The longevity diet is not a dietary restriction intended to only cause weight loss but a lifestyle focused on slowing aging, which can complement standard healthcare and, taken as a preventative measure, will aid in avoiding morbidity and sustaining health into advanced age,” says Longo [2].”

[1] https://pubmed.ncbi.nlm.nih.gov/35487190/
[2] https://gero.usc.edu/2022/04/28/valter-longo-longevity-diet/