Links: Go to episode page (with links & resources) Subscribe to Sigma Nutrition Premium Receive our free weekly email, The Sigma Synopsis About This Episode: Often claims are made recommending that people should aim to keep peaks in blood glucose low in terms of both magnitude and frequency. And while many claims about blood glucose “spikes” are incorrect or purposefully exaggerated to grab attention, there are some reasonable and interesting hypotheses put forward in relation to blood gluco...
Mar 13, 2023•1 hr 23 min
Links: Episode page (with more links) Subscribe to Premium Introduction Depression is a common disorder and is a leading cause of disability worldwide. Depression results from a complex interaction of social, psychological, and biological factors. Diet has been one area that has been suggested in playing a role; from potential for exacerbating symptoms to being a treatment. And while some associations have been noted, many claims far exceed what (little) evidence exists. Online it is common to s...
Mar 07, 2023•1 hr 13 min
Links: Subscribe to Premium Go to this episode's page (with links) Live event: London - March 18th Receive 'Sigma Synopsis' emails Description: When thinking about the effect of eating or not eating a certain food or nutrient, we can’t consider this in isolation. Meaning, we need to evaluate the impact within the context of what such an inclusion/exclusion does to an individual’s overall diet pattern. Thinking about this concept, the phrase “compared to what?” has been colloquially used. And whi...
Feb 28, 2023•53 min
Links: Episode page Subscribe to Premium Live Event: London, UK Receive the Sigma Synopsis emails About This Episode: Does sodium lead to calcium losses? Do high-salt diets harm bone health? At what thresholds could there be an impact? Does any of this change our recommendations around salt/sodium intake? Thanks to Sigma Nutrition Premium subscriber Kate Wall for submitting a question in the member’s area that inspired this episode. Kate asks: “Salt can impact calcium excretion in the urine and ...
Feb 21, 2023•58 min
Links: Subscribe to Premium Episode page Description: Nutritionists, dietitians and other health & fitness professionals face many challenges when attempting to help their clients and in understanding what approaches are best in a given situations. There are often discussions around improving client adherence to dietary recommendations. However, sometimes we need to think deeper about this topic. Is there really just a tool to fix this? Or could the problem be the recommendations themselves?...
Feb 14, 2023•10 min
Links: Episode page Subscribe to Premium Live event in London, UK Description: Meal timing has been a popular, and at times controversial, topic of interest in nutrition. Despite much speculation over the years as to potential advantages to specific meal timing or meal frequencies, for many outcomes there seems to be little pragmatically meaningful difference. For example, when accounting for calorie and macronutrient intake, there is little to no effect of meal timing on body composition, blood...
Feb 07, 2023•1 hr 11 min
Research in the field of ‘chrononutrition’ has continued to grow in the past couple of years, with some important studies being published in recent times. Chrononutrition is a research area that looks at the relationship between temporal (time-related) eating patterns, circadian rhythms, and metabolic health. While past podcast episodes have covered various aspects of chrononutrition, the latest research has added important pieces to the puzzle and has lead to both Alan and Danny updated their v...
Jan 31, 2023•1 hr 18 min
There is almost universal agreement that excess added sugar in the diet is detrimental to health. However, much of this negative health impact clearly relates to the ability of high sugar intakes to drive excess calorie intake and fat accumulation, which cause health issues. But what about situtaions of where there is not a calorie surplus (hypercaloric diet) or weight gain? Some people claim that sugar is inherently damaging. While others push back and claim sugar is only a problem in the conte...
Jan 24, 2023•1 hr 34 min
This episode brings you a “debate” between Danny Lennon and Dr. Jackson Peos on the utility of intuitive eating. Specifcally, they make a case for and against, respectively, for the position: “Intuitive eating can be recommended eating approach for those with fitness and/or physique goals”. This episode is a Premium-exclusive episode, so you’ll need to be a Premium subscriber to listen to the full discussion but you can hear a preview here. Links: Subscribe to Premium Live event: London, UK - Ma...
Jan 17, 2023•12 min
Iron is an important nutrient for athletes, given that it is used for oxygen transport and energy production. However, research on athletes often reports a relatively high prevalence of iron deficiency. Common symptoms of low iron status like lethargy, fatigue and negative mood states are naturally of concern to athletes. But there is also the potential for low iron to directly impact work capacity. Therefore, maintaining adequate iron status (and knowing the signs of iron deficiency) is crucial...
Jan 10, 2023•51 min
Iron deficiency is a prevalent issue. Worldwide, it is the leading nutritional deficiency. And although there is lower prevalence in high-income countries, a significant number of people are still affected. Iron deficiency may be a result of too little iron coming in (i.e., via diet choices or low absorption), or from excess losses (e.g., commonly from blood losses). Understanding how these can impact iron status is crucial for both accurate diagnosis and treatment. In relation to dietary iron, ...
Jan 03, 2023•1 hr 1 min
Iron is involved in a whole range of biological processes and a consistent supply of iron is crucial for cellular turnover. But despite iron being an essential mineral for human function, it is highly toxic to cells and tissues if present at high levels. Therefore an intricate and tight regulation of iron is necessary. If iron status gets too low, iron-deficiency anaemia can result. In such situations there is a shortfall in hemoglobin production, which leads to a range of issues in the body. So...
Dec 27, 2022•1 hr 20 min
The current food environment is continuously highlighted as a problem for public health. And so there is a strong focus in both public policy and research circles to determine which strategies could lead to a healthier food environment. One potential strategy that is widely recommended by public health experts is the use of fiscal/taxation policies to decrease the consumption of unhealthy foods and beverages. By making unhealthy foods and beverages relatively more expensive than healthy foods an...
Dec 20, 2022•45 min
In October 2022, Ruddick-Collins et al . published results of an RCT looking at the impact of different calorie distributions across the day. This study was from the ‘Big Breakfast Study’ project, primarily from the University of Aberdeen. In this study, 30 subjects underwent two 4-week calorie-restricted diets that were matched for calories. One diet was “morning-loaded”, meaning that daily calories were distributed as 45% at breakfast, 35% at lunch, and 20% at dinner. The other was “evening-lo...
Dec 13, 2022•30 min
In this episode, the Sigma team explores the question: “Do vegan diets increase the risk of depression?” This is a question that emerges from a few different places. First, it’s common to hear such a claim from proponents of largely animal-based diets. Some reference is often made about how vegan diets can, at best, worsen symptoms or, at worst, even cause depression. Or conversely, they may state that moving away from a plant-based diet will improve mental health outcomes, including depression....
Dec 06, 2022•1 hr 42 min
Links: Show notes page (incl. study links & related episodes) Subscribe to Sigma Nutrition Premium Live event in London, UK About this episode: Over the past decade, the increasing uptake and acceptance of the Nova food processing classification system has placed focus on one of the categories in Nova; ultra-processed foods (UPFs). Ultra-processed foods (UPFs) are products created from deconstructed (and recombined) food components, usually with the goal of creating a highly palatable, conve...
Nov 29, 2022•1 hr 10 min
Research has shown that food marketing strongly impacts children’s eating behaviour. Marketing influences food purchase requests, purchases, and preferences. And the evidence of a relationship between food marketing exposure and obesity meets epidemiological criteria for causality. The evidence suggests that the impact of food marketing is a function of both exposure to the marketing message and its persuasive power. What does the current evidence tell us about the exact effect of marketing on f...
Nov 22, 2022•1 hr 1 min
Never before has there been greater access to information about nutrition and health. But never before has there been such a low barrier to being seen as an “expert”. There are large numbers of people getting information from, and basing their health decisions on, people who don’t have direct expertise in the field in which they are talking about. Moreover, some promote the lack of domain expertise as a feature, not a bug. They claim that those that were conventionally seen as domain experts are...
Nov 15, 2022•33 min
Obesity increases the risk of a range of chronic diseases and negative health outcomes. And trials where a sufficient amount of weight loss is achieved show health improvements. However, despite the “straightforward” nature of causing weight loss through a hypocaloric diet, it is clear that most people who lose weight will regain some or all of the weight. This is a result of both the physiologic control of intake and expenditure (i.e. homeostatic regulation by the body to avoid staying at a low...
Nov 08, 2022•56 min
The endocrine system plays a central role in growth, development, metabolism, reproduction, and physical well-being throughout life. Hormones interact in complex networks, orchestrating a range of critical functions. Over the life course, we experience various changes in hormone levels, fluctuations, patterns, and actions. Additionally, lifestyle factors and disease processes can impact the levels and functions of hormones. In this episode, Dr. Nicky Keay, a medical doctor with expertise in the ...
Nov 01, 2022•52 min
Stable isotopes have been used as tracers in human nutritional studies for many years. But what are they? Why do we use ‘tracers’ in nutrition studies? And what are some practical examples? A chemical element can have different forms or ‘isotopes.’ These different isotopes have the same atomic number and position in the periodic table but have different atomic masses and physical properties. An isotope that is not radioactive is said to be ‘stable’. In physiology and metabolism research, stable ...
Oct 25, 2022•12 min
Given the negative consequences of consistent overconsumption of food (leading to a caloric surplus), having a dietary intake that is of appropriate calorie intake is an important aspect of long-term health. Therefore, thinking about which foods and diets can help promote appropriate satiety to keep calorie intake in check is a key focus for many researchers and practitioners. There is a complex system of human appetite control. This appetite system influences food consumption and associated mot...
Oct 18, 2022•1 hr 36 min
Hypertension (elevated blood pressure) is a condition that significantly increases the risk of several diseases and is a major cause of premature death worldwide. In the US, recent estimates suggest that about half of the adult population has hypertension. At a population level, high sodium intake is one of the main dietary risk factors. All population health guidelines recommend keeping sodium intake below certain levels. While, on average, blood pressure correlates with sodium intake, there is...
Oct 11, 2022•1 hr 10 min
Exercise improves metabolic control both via increasing muscle glucose uptake during muscle contractions by insulin-independent mechanisms and by increasing skeletal muscle insulin sensitivity after physical activity. A reduction in skeletal muscle insulin sensitivity is an early event in the development of not only prediabetes, metabolic syndrome, and type 2 diabetes but is also associated with other conditions such as cardiovascular disease and some cancers. One of the researchers that has bee...
Oct 04, 2022•1 hr 3 min
The term ‘tactical populations’ has been applied to those working in law enforcement, fire, first responders, and military. In addition to the importance of their work, the work they do itself presents some challenges for health and nutrition. Despite the fact that such individuals make up a significant number of the population and their work plays a crucial role in society, there is currently very little research on fire and law enforcement nutrition. Most research is on the prevalence of disea...
Sep 27, 2022•47 min
In this Premium-exclusive ‘Ask Me Anything’ episode, Alan & Danny answer a range of listener questions. Topics include obesity rates, lowering blood pressure, cholesterol drugs, PCOS, and what issues they have changed their minds on. See the full list of questions below. [02.37] Do you feel that there is hope (or an effective way forward) for obesity rates to come down? Based on your response, why/why not? [11.28] In this field, it seems like so many of us have had positions we’ve held very ...
Sep 20, 2022•15 min
When it comes to eating to promote muscle hypertrophy, muscle repair/recovery and maintenance of mass and function, protein has been an obvious focus. Indeed muscle mass and quality are dependent on the continuous remodeling of skeletal muscle proteins. This is related to the amount of muscle protein balance, i.e. the net difference between muscle protein synthesis (MPS) and muscle protein breakdown (MPB). Because of this, MPS has long been used as a proxy measure for muscle repair and/or growth...
Sep 13, 2022•1 hr 25 min
The brain plays a central role in both physical and psychological function and performance. The brain also has a very high energy demand. In addition, fatiguing conditions can cause impairment of cognitive performance. One area of research in neurometabolism related to the potential use of nutrients on improving cognitive function, as well as “rescuing” the fatigue-related declines in performance. Nick Gant is Director of the Exercise Neurometabolism Laboratory at the University of Auckland. His...
Sep 06, 2022•1 hr 12 min
This episode was oringally published as one of our “Expert – ask me anything” (AMA) episodes, which we published for Premium prescribers. In such bonus episodes, we collect questions from Premium subscribers and ask them direct to a world-class expert and past podcast guest. If you’re interested in subscribing to Sigma Nutrition Premium, then check all the details here . In this episode Prof. Stu Phillips takes questions about synethized whey protein, plant proteins, post-exercise MPS, and many ...
Aug 30, 2022•56 min
It has been consistently shown in research that elevated dietary sodium consumption is associated with high blood pressure and an increased risk of cardiovascular disease. In addition, low levels of dietary potassium intake are associated with these same risks. However, there is some debate on how to characterize these relationships. In a study published in European Heart Journal in July 2022, using data from the EPIC-Norfolk study, researchers attempted to answer whether the associations betwee...
Aug 23, 2022•56 min
