Sigma Nutrition Radio

With the advances in understanding the importance of the gut (including its bacterial contents) for human health, much interest and attention has been placed on how to eat to promote positive 'gut health'. This has led to many exciting research questions and labs doing fascinating work. However, on the opposite side, it has led to a spike in opportunistic quacks to jump on the wave of enthusiasm and promote diets, supplements, testing kits and products that don't reflect the current evidence base. So what do we actually know? What aspects of diet should we focus on to improve gut health? For those with gut symptoms (bloating, pain, irritable bowel, etc.) is it possible to include more vegetables and fiber without the pain? In this episode, gut health researcher at King's College London, Dr. Megan Rossi, discusses some simple heuristics to follow that will likely improve overall health, and promote positive gut health. Access show notes here Subscribe to Premium

A study published in March 2022 suggested that consumption of artificial (non-nutritive) sweeteners is associated with a 13% increase in risk of cancer. And so in this episode, Dr. Alan Flanagan, Dr. Niamh Aspell, and Danny Lennon discuss this specific study and give their thoughts on what are fair conclusions to come to. Access show notes here Subscribe to Premium here

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 to mechanistic research. Another is the limitations of RCTs for nutrition-specific research questions. In this episode, Prof. Temple discusses these issues, as well as what strategies can actually improve population diet, and thus health. Access show notes here Subscribe to Premium here

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

Neurodegenerative disease and obesity neuroscience expert, Stephan Guyenet, PhD, answers questions on the impact of liposuction on hunger, effects of chronic energy restriction on appetite hormones, dysregulation versus normal regulation of body mass, and the benefits of Sigma Nutrition Premium.

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, droughts, more intense hurricanes, heatwaves and wildfires can drive down crop yields, destroy livestock, and interfere with the transport of food. And rising carbon dioxide levels from human activity can make staple crops like rice and wheat less nutritious. In this podcast the Sigma team take a look at the evidence on how climate change will impact nutrient status, if left unchecked. There will be also a look at what solutions have been put forward to tackle this issue. This episode will focus more on how climate change impacts nutritional & nutrient status, as opposed to converse (but equally important) issue of how food systems impact climate change. Access show notes here Subscribe to Premium here Attend a live event in London, Dublin or Berlin!

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 include: the impact of menstrual cycle phase on cravings, at-risk nutrients in pre-menopausal women, functional hypothalamic amenorrhea, interaction of diet and PMS, the physiological changes at menopause and potential role of diet. Click here for show notes to this episode Click here for Premium Click here for live event details

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 specifially how it applies to evaluating nutrition research and coming to conclusions for practice. GRADE (Grading of Recommendations, Assessment, Development and Evaluations) is a framework for developing and presenting summaries of evidence and provides a systematic approach for grading the quality of evidence and making clinical practice recommendations. In order to listen to the full episode, you will need to subscribe to Sigma Nutrition Premium.

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 impact of folate insufficiency/deficiency, genetics variatnts of the MTHFR gene (and other genes) that impact folate metabolism, and the impact of folate on health outcomes; including heart disease, birth defects, cancer, and brain health & cognition. Detailed study notes and transcript to this episode

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: What is the connection between choline and DHA? What is the PEMT pathway? Study design for the choline + DHA trial Are there risks of high-dose choline? Main findings of the trial How DHA status is not just a function of DHA intake, but also methyl metabolism too Issues with omega-3 trials; e.g. not taking baseline status into account Pragmatic recommendations for health professionals and patients Different forms of choline supplements Choline supplementation vs. food-derived choline Access the show notes here Subscribe to Premium here