Sigma Nutrition Radio-logo

Sigma Nutrition Radio

Fitness and Nutrition

Discussions about the science of nutrition, dietetics and health. The podcast that educates through nuanced conversations, exploring evidence and cultivating critical thinking. Hosted by Danny Lennon.

Discussions about the science of nutrition, dietetics and health. The podcast that educates through nuanced conversations, exploring evidence and cultivating critical thinking. Hosted by Danny Lennon.




Discussions about the science of nutrition, dietetics and health. The podcast that educates through nuanced conversations, exploring evidence and cultivating critical thinking. Hosted by Danny Lennon.






#448: Prof. Norman Temple – Can Science Answer Diet-Health Questions?

While we’ve never known more about diet and health, there remain many unanswered questions in nutrition science. However, there is often disagreements on how best to answer these questions, particularly in relation to informing practical diet advise that meaningfully improves health. Prof. Norman Temple is one academic who has written on a number of these issues. One issue he highlights is the large discrepency in the practical value we have attained from cohort studies and RCTs, relative...


#447: Does Eating Fish Increase Skin Cancer Risk? Study Analysis

A recent study reported a higher risk of developing melanoma in people who ate a relatively high intake of fish. This study caused headlines and it was picked up by many outlets (including the New York Times, Sky News, etc.). In this episode, Alan and Danny dig into the nuances of this study to see if the headlines are justified. Click here for show notes Click here for Premium


Live Events in London, Dublin & Berlin

Tickets are on sale now for our live events later this year. Tickets are first come, first served and are priced at £35/€40 for general admission. Full details here:


PRE #7: Stephan Guyenet, PhD - Ask Me Anything!

This is an “ask me anything” (AMA) episode, which means a world-class expert and past podcast guest comes on the podcast to answer questions submitted by you, our podcast listeners. Stephan Guyenet spent 12 years in academia studying neurodegenerative disease and obesity neuroscience. He was a postdoctoral fellow at the Univeristy of Washington, studying the neuroscience of obesity and eating behavior. Previous to that he completed a PhD in neuroscience. Stephan is the author of the...


#446: How Climate Change Impacts Nutrient Status

Climate change refers to long-term shifts in temperatures and weather patterns. These shifts may be natural, such as through variations in the solar cycle. But since the 1800’s, human activities have been the main driver of climate change, primarily due to burning fossil fuels like coal, oil and gas. Climate change has the potential to negatively impact the nutrient value of plants, soil organisms, food stuffs, via a variety of ways. Climate change puts food supplies at risk. Floods,...


#445: Dr. Hazel Wallace - Nutrition for Women’s Health

When it comes to specific questions related to diet and health for women, there is often a shortage of consensus answers from research, for a variety of reasons. In addition, there are clearly aspects of biological sex that have implications for health and also the interaction with diet. For example, the impact of the menstural cycle, of menopause, and differences in nutrient requirements. In this episode, Dr. Hazel Wallace discusses some of these key considerations. Some things covered...


PRE #6: GRADE System: What is it? And How Does it Apply to Nutrition? [Preview]

This is a preview of the second episode in a new series called “Nutrition Science Explained”, in which members of the Sigma team will take a concept commonly mentioned in discussions about nutrition science, and explain what it is, give more background context, and highlight important aspects to know. The goal is to aid listeners to have a deeper understanding of other episodes when such concepts are mentioned. In this episode Alan Flanagan discusses the concept of the GRADE system, and...


#444: Folate – Intake, Genetics & Health Outcomes

Folate (also known as viatmin B9) actually relates to a collection of folates; both natural dietary folates and synthetic forms, primarily folic acid. This folate/folic acid that is consumed via the diet or supplementation is a precursor for the formation of tetrahydrofolate (THF), which is a carbon donor and acts a cofactor for a number of enzymes that play important roles in several processes. In this episode, Alan and Danny discuss the role of folate in the methlyation cycle, the...


#443: Kevin Klatt, PhD, RD - Can Choline Help Improve DHA Status?

A recently published study by Klatt and colleagues examined the impact of choline supplementation alongside DHA supplementation, versus DHA supplementation alone, on DHA status in pregnancy. It is known that DHA is a critical nutrient at this time for healthy development of the child. And through a number of mechanisms discussed later, it has been hypothesized that choline could lead to greater DHA status. We discuss: Access the show notes here Subscribe to Premium here


#442: Are Vegetables Detrimental to Health?

In this episode Alan and Danny aim to address the idea that you shouldn’t eat vegetables, or that they aren’t beneficial. We will specifically look at a number of claims that relate to: This episode was orignally published to Sigma Nutrition Premium. If you wish to get more of these Quack Asylum episodes (and lots of other features, including detailed study notes) then subscribe to Sigma Nutrition Premium. Click here to access show notes


PRE #5: Prof. Stuart Phillips - Ask Me Anything! [Preview]

This is an "ask me anything" (AMA) episode, with Prof. Stuart Phillips of McMaster University. Prof. Phillips takes questions on protein intake, sources, muscle function, and healthy ageing. To listen to the full AMA, click here to subscribe to Sigma Nutrition Premium. Questions answered: Subscribe to Premium


#441: Julie Abayomi, PhD, RD - Diet During Pregnancy

Consuming a healthy diet during pregnancy is an obvious and accepted recommedation. However, what exactly is a "healthy diet" in this context? In addition, there are specific nutrients which are crucial for the healthy development of the child, including nutrients which may be difficult to consume enough of. In addition there are nutrients and foods that need to limited or avoided during this period. In this episode, researcher and dietitian Dr. Julie Abayomi discusses important nutrients...


#440: Are Dietary Guidelines Trying To Kill Us?

It has become common rhetoric for those promoting various types of diets to suggest that dietary guidelines published by government departments are at best, unhealthy, or at worst, causative in driving obesity and chronic disease in the population. While different countries and organizations produce their own guidelines, with slight differences, most of the conversation has focused on the Dietary Guidelines for Americans, that are created by the USDA. Often the claims is that following...


PRE #4: Detoxification Protocols [Preview]

There have been many claims made about the benefits of a detoxification "protocol" or "plan", based on specific dietary and supplemental regimens. Many of the arguments propose that many things we come into contact with are toxins and they can accumulate and compound in effect over time, causing a range of issues. Therefore, by removing these toxins (via a “detoxification protocol”), we can have better health. And indeed it is well known that there are a large number of toxins in the...


#439: Prof. David Jenkins - Lipid-Lowering Diets

With elevated LDL-cholesterol being a causal risk factor for atherosclerotic heart disease, having interventions to lower blood lipids, and in particular LDL-C, are crucial for population health. A number of drugs are now incredibly effective for this, with statins being the most widely used. However, for those who do not wish to take a medication and/or have only a mild elevation, there may be potential for dietary intervention to lower LDL-C to a point where a statin (or other drug) is...


#438: Diet, Brain Health & Cognitive Function

Some cognitive decline is normal with age. However, more significant cognitive decline is primarily due to disease-induced dementias (such as Alzheimer’s Disease). It also results from neurodegenerative disorders and chronic, prolonged degeneration of our neuronal pathways and functions. Drug discovery for dementias have been largely unsuccessful, leaving no good treatments for this collection of diseases. This had led to research examining areas that may aid in preventing (or more...


#437: GMOs & Genetic Engineering: Harmless or Health-Hazard?

The issue of genetic enginnering in the food system is one that is often charged with emotion and strong opinion. Indeed, there has been much concern voiced over the years about the potential harms to both human health and the environment of genetically-modified (or more accurately, genetically-engineered) crops. Some concern takes the form of outright hysteria, while other concerns are more nuanced and subtle. Among these concerns, which have good evidence to support them? What...


#436: Charlene Van Buiten, PhD – Coeliac Disease & the Search for Novel Therapies

Coeliac disease is an autoimmune disorder stimulated by the ingestion of gluten, a protein found naturally in wheat, barley and rye. The condition affects approximately 1% of the Western world. However, currently the only approved treatment for coeliac disease is adherence to a gluten-free diet for life. Therefore there is much research underway to develop alternative treatment options that may help these patients. One novel antigen-focused therapy that has been hypothesised is the use of...


#435: Fasting & Longevity – Does the Evidence Match the Hype?

Current discussions relating to health focus on longevity. This may include some who look at lifespan extension, some who talk of delaying or “treating” ageing or those who focus on reducing morbidity within the parameters of normal lifespan. One propsed intervention that has garnered a lot of excitement, owing to some interesting research, is the potential use of fasting to increase longevity and/or healthspan. Within this broad category, various different dietary interventions have been...


PRE #2: "Fish is Bad For You" [PREVIEW]

While dietary guidelines universally include fish as a food group that can be consumed regularly in a healthy dietary pattern, there are some potential risks of fish consumption that get raised. Some have some legitimacy, for example the frequency of consumption of high-mercury fish. However, other claims can go to extremes ("eating fish is bad for you") that are based in ideology rather than evidence. In this Quack Asylum episode, we use a video made by a medical doctor as an example of...