Diet and Longevity: Exploring the Impact

Diet is the behaviour that’s been studied the most in terms of trying to affect things like aging and longevity. And what scientists end up leaning on is what we call ‘epidemiological’ or observational data. They compare the diets that different people eat, and then they look at the features of those people using things like biological aging or disease risk or life expectancy. Do certain diets tend to correlate with certain outcomes?

There are really three components of diet that seems to be impacting aging: So the first is how much we eat, the second is what we eat, and the third is when we eat. A lot of science went into the idea of calorie restriction. Calorie restriction isn’t starvation, it’s usually just about 20% reduction in the overall calorie intake. In a lot of different animal models, anything from a worm to a mouse, people have seen that when animals are caloric restricted, they tend to live longer.

The other thing that’s been studied is the concept of what we eat. A lot of research has gone into whether things like a plant-based diet are actually beneficial to aging and longevity. And there seems to be some evidence that eating less animal products, more fruits and vegetables, more whole foods is better overall.

This is the third thing comes down to when we eat, and this is really a new field in aging and longevity science. So again, most people aren’t able to restrict the calories from their diet, but what scientists have found is that fasting can actually mimic some of the benefits that we’ve seen with caloric restriction. So if people can perhaps minimize their eating to a small window, we think that this can actually recapitulate a lot of the benefits that we’re seeing in the calorie restriction studies.

The idea of why things like calorie restriction or fasting might actually improve our aging process is because we think this evokes this idea of ‘hormesis’ in our bodies. What hormesis refers to is a mild stressor that actually makes our bodies more resilient and robust to stress over time. So, having these short – term mild stressors, whether it be a small caloric deficit, actually makes our bodies more resilient against a lot of the changes we see that increase with aging.

It’s not that easy to figure out what the optimal or ideal diet is for each of us, and we don’t know exactly how things, like genetics, are going to predispose people to different diets. But one way to do this is to keep track of things like our biological age, which sees how our diet is affecting us. So, if you were to completely change your diet or introduce something like intermittent fasting, do you see that reflected on your body? People who are older and more prone to things like muscle loss or weakness might actually need more protein than people who are younger, whereas science has shown that a low protein diet might be beneficial.

So, it’s important to keep in mind that these things aren’t set in stone, and they really need to be considered in a personalized basis. As we move forward in the science and develop more of these biomarkers of aging, I think this will really accelerate our understanding of how diet impacts the aging process. Our lifestyle and our behaviours are actually going to be the biggest contributors to how fast we’re aging.