Are you interested in learning about an easy, inexpensive way to add many healthy years to your life? Something that is grounded in ancient wisdom and growing scientific research and is accessible to almost everyone. In this episode, I’m talking about diet, one of the foundational pillars of health and longevity. And I’m exploring not just what we should eat but also when we should eat and how getting these two things right can have such a positive impact on our health and how long we live. Full Episode Transcript 00:00:45 So here’s a question for you. Are you interested in learning about an easy, inexpensive way to add many healthy, active years to your life? Potentially decades! I'm not talking about some expensive new supplement or the latest fad diet. I'm talking about something that is grounded in ancient wisdom and growing scientific research. In this episode, I’m talking about food, the second foundational pillar of health and longevity — the first pillar being sleep, which I covered in the last episode and the third being movement and exercise, and I find it helpful to remember these three pillars as SLEEP, EAT AND FEET. But today is about food and I’m exploring not just what we eat but also when we eat and how getting these two things right can have such a massively beneficial effect on our health and can slow down and possibly even reverse the ageing process. 00:01:47 1. CAN EATING LESS OFTEN HELP YOU LIVE LONGER? So, I want to kick this episode off by focusing first on not what we should eat but when we should eat. And let's start with a fundamental principle of longevity that might surprise you: eating less often might help you live longer. Yes, you heard me right. One of the most consistent findings in longevity research in recent years, is that giving your body regular breaks from food can trigger powerful rejuvenation processes. Throughout human evolution, our bodies didn't evolve with the expectation of constant food availability. Three meals a day plus snacks is actually a very recent development in human history. Our ancestors experienced regular periods without food—sometimes by necessity, sometimes by design. Research now shows that these fasting periods are far from harmful—they actually trigger a cascade of repair and rejuvenation processes in the body. When we're constantly fed, our bodies are stuck in growth and reproduction mode. Our cells are like, yeah, life is good we’ve got plenty of readily available nutrients, let’s just kick back and relax guys. But in this euphoric state our cells can fail to spot things that are going wrong in the background – like the build up of toxins and the formation of cancerous cells. Things that, left unchecked are going to start damaging our bodies and cut our lives short. Basically, constant eating causes our cells to get a bit complacent. But when we starve our bodies of nutrients for a while we shift into repair mode. And our cells are like, hang on a minute guys, we aren’t being fed! We need to batton down the hatches and go into survival mode. And in this state, they effectively go on guard and actively hunt down any bad stuff that’s hanging around and dispose of it. Now clearly, it is a far more scientific process than this and I’ll go into some of the more nerdy stuff in a minute but this is my laymans explanation and it helps me to easily get my head around it. And this isn't just a theory. Studies across multiple species, from yeast to primates, show that controlling food intake patterns can extend lifespan. And the evidence in humans is increasingly compelling. 00:04:13 2. EATING LESS CALORIES AND EATING LESS OFTEN CAN HELP YOU LIVE LONGER Let's talk about why reducing calories or simply extending the length of time we go without food works at a biological level. Caloric restriction means reducing overall food intake without malnutrition and it is one of the most consistently effective anti-aging interventions across species. In the 1930s, researchers discovered that rats fed fewer calories lived significantly longer than their well-fed counterparts. Since then, similar findings have been shown in yeast, worms, flies, mice, and even preliminary studies in primates. What's remarkable is how conserved this mechanism is evolutionarily and by conserved, I mean how it has been passed down through the generations in our genes. The same pathways that respond to reduced calorie intake in a simple yeast cell appear to work in very similar ways in human cells. This suggests we're looking at a fundamental biological process that evolved very early and has been maintained across species. So why would this be? The leading theory is that when food is scarce, organisms shift resources from reproduction and growth to maintenance and repair. So as I mentioned a moment ago, It's as if the body says, "Times are tough, let's focus on surviving longer until conditions improve." Now I can guess what you might be thinking. Your thinking, great Tim, so your just telling me I need to eat less, tell me something I don’t know. Because we all know that reducing calories is much easier said than done. The good news is that you don't necessarily need to reduce your overall calories to get many of these benefits. Emerging research suggests that when you eat might be just as important as what you eat or how much you eat. 00:06:17 3. FASTING IS ACCESSIBLE (AND SAVES MONEY!) Here's something I love about fasting-based approaches to longevity: they are accessible to almost everyone. Unlike expensive supplements or other lifestyle interventions, eating less costs nothing. In fact, you'll likely save money because eating within a smaller time-window often means we can’t cram as much food in! But of course, what you put into your body is also very important and the fundamental strategy is: eat less frequently, focus on nutrient-dense, natural foods and give your body regular breaks from digestion. Don’t think of this as deprivation. It's about optimization. Many people who adopt time-restricted eating or intermittent fasting report not only better health markers, for the ones that are actively measuring and monitoring, but also increased energy, mental clarity, and a healthier relationship with food overall. And I want to emphasize that caloric restriction or fasting, isn’t about starving yourself. It’s about finding a sustainable pattern that works for your body and lifestyle. For some, that might mean a 16-hour daily fast. For others, it could be a more moderate 12-hour overnight fast. And for others still, it might mean occasional longer fasting periods. The key is consistency and listening to your body and probably mixing things up every once in a while to stop our cells getting complacent. 00:07:48 4. A LOW ENERGY STATE TRIGGERS GENETIC ANTI-AGING PATHWAYS So, let's get a bit more technical now and explore what happens in your cells when you fast. When you restrict your eating window or reduce calories, your body experiences a mild energy stress, also known as hormesis or hormetic stress. This triggers several genetic pathways that are associated with longevity and cellular protection. One of the key players in this process is a family of proteins called sirtuins. These are sometimes called "longevity genes" because they appear to play a central role in regulating lifespan across different species. Sirtuins act as cellular sensors, detecting energy levels and stress, and coordinating appropriate responses. When activated by fasting or caloric restriction, they help repair damaged DNA, regulate inflammation, improve mitochondrial function, and facilitate cellular cleanup processes. In particular, SIRT1—the most studied sirtuin in mammals—helps cells adapt to stress and may delay age-related decline. Studies show that mice with higher SIRT1 activity live longer and stay healthier. The fascinating thing about sirtuins is that they seem to be the link between our lifestyle choices and our genetic destiny. They respond to environmental cues like food availability and translate them into cellular actions that can either accelerate or slow aging. 00:09:25 5. NAD+ IS ELEVATED BY A LOW ENERGY STATE For sirtuins to work properly, they need a critical cofactor called NAD+, or nicotinamide adenine dinucleotide. And you can think of NAD+ as a helper molecule in our bodies that binds to other molecules to help with molecular reactions. NAD+ is essential for hundreds of biological processes, especially those related to energy metabolism. Here's where it gets really interesting: Because our bodies don’t have an endless supply of NAD+ and our levels naturally decline as we age, which may contribute to age-related dysfunction. But fasting elevates NAD+ levels, giving sirtuins the fuel they need to do their job effectively. When you fast, your cells shift from using glucose as their primary fuel to using fatty acids and ketones. This metabolic switch increases the ratio of NAD+ to NADH, effectively boosting sirtuin activity. This helps explain why fasting seems to have such broad benefits. By increasing NAD+ and activating sirtuins, fasting doesn't just affect one tissue or system—it triggers a coordinated response throughout the body that promotes resilience and repair. So you’re probably thinking that it sounds like it would be a smart move to try and increase the amount of NAD+ in your body, and you’d be right. So how do we do this? Well, you can buy NAD+ boosters to increase the amount of NAD+ in your system but these aren’t terribly effective due to poor absorption of supplemental NAD+. Now, with further research and development these may become more effective but currently, the most reliable way to boost NAD+ currently, seems to be through lifestyle approaches like fasting, exercise, and getting adequate amounts of what we call NAD+ precursors from food. The next question is:
