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SNP20: The Cumulative Exposure Model of LDL-C & Heart Disease Aug 22, 2023

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This is a Premium-exclusive episode, so here you'll only hear a preview. In order to listen to the full episode you'll need to subscribe to Sigma Nutrition Premium.

About This Episode:

It has been clearly demonstrated that elevated LDL-cholesterol (LDL-C), or perhaps more specifically pro-atherogenic lipoproteins, is causal in atherosclerosis development in humans.

One crucial concept within this is that the risk relates not only to the magnitude of elevated LDL-C, but the duration of exposure. Thus, the role of LDL-C in driving atherosclerosis is referred to as a "cumulative, integrated exposure over the lifecourse".

But, what exactly does this mean?

In this episode, Danny discusses the cumulative exposure model of LDL-C in atherosclerosis, the evidence supporting it, and the implications of this for the "debates" that get raised in relation to LDL-C (or apoB-containing lipoproteins) and heart disease.

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#492: How Does Weight Cycling Impact Long-term Health? Aug 15, 2023

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About This Episode:

Losing at least 5% of one's initial body weight is associated with improvements in glycaemic control, blood pressure, triglyceride levels, and other positive outcomes. Due to these reasons, it is typically recommended that individuals classified as overweight or obese should engage in effective weight loss interventions.

However, despite the potential for clinically significant weight loss through these interventions, weight regain is a common occurrence. This can be attributed to a combination of low adherence to weight control strategies and compensatory physiological mechanisms that influence weight regain.

Consequently, this may result in a cycle of losing and regaining weight over the long term, which is commonly referred to as "weight cycling."

There are concerns regarding the potential harm to health and increased risk of chronic diseases associated with weight cycling. Some mechanisms have been proposed, such as the loss of lean mass during weight loss periods that is not regained when weight is regained. However, the evidence supporting the harmful effects of weight cycling on health is incomplete and many unanswered questions remain.

In this episode, we will examine the evidence published to date and draw evidence-based conclusions regarding the impact of weight cycling on long-term health.

#491: Do High Protein Intakes Cause Insulin Resistance? Aug 08, 2023

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About This Episode:

There has been interest in, and debate about, how protein intake impacts metabolic health, particularly in relation to insulin resistance and type 2 diabetes risk.

Recently, there has been interest in higher protein intakes as an intervention in diabetes, owing to a variety of potential mechanisms. For example, the satiety value of protein, the promotion of insulin secretion by protein, and imapcts on incretin hormones.

However, others have warned against high protein intakes. With some going as far as to claim high, or even moderate, protein intakes can lead to insulin resistance or negatively effect beta-cell function.

In this episode, we look at the research typically cited in support of such claims, and dig into the details. We consider the overall evidence in this area to answer the question 'do high protein diets cause insulin resistance or increase diabetes risk?'.

#490: How Does Exercise Impact Beta-cell Function in Type 2 Diabetes? – Mark Lyngbæk, MD Aug 01, 2023

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About This Episode: The management of type 2 diabetes has long been a challenge, but a new study conducted by researcher Mark Lyngbaek and his colleagues has the potential to add important considerations to the approach to treatment. Titled the "DOSE-EX" randomized clinical trial, their study uncovers the impact of exercise and weight loss on beta-cell function, a key factor in diabetes progression. DOSE-EX is a four-armed randomized trial involving 82 individuals with newly diagnosed type 2 diabetes. The participants were divided into four groups: standard care, calorie restriction, calorie restriction with exercise three times per week, and calorie restriction with exercise six times per week. Over a span of 16 weeks, the researchers assessed the effects of these interventions on beta-cell function using various indicators. The study's findings are incredibly interesting, demonstrating that exercise in combination with diet-induced weight loss leads to a substantial improvement in glucose-stimulated beta-cell function. Importantly, the results indicate the importance of considering both: a) the exercise dose, and b) the methodology of assessing beta-cell function, when evaluating intervention effectiveness. In this episode, Dr. Lyngbaek will elucidate the implications of these findings for the management of type 2 diabetes. We will explore the potential of exercise as a therapeutic tool, its optimal dosage, and the considerations for integrating it into individualized treatment plans. About The Guest: Dr. Mark Lyngbæk is a physician, currently in an introduction position at the Department of Rheumatology and Internal Medicine 2 at Holbæk Hospital, and also a PhD student at the Centre for Physical Activity Research at Rigshospitalet. His research has looked at exercise, beta-cell function and type 2 diabetes. He is supported by a research grant from the Danish Diabetes Academy, which is funded by the Novo Nordisk Foundation (grant number NNF17SA0031406). The Centre for Physical Activity Research is supported by TrygFonden (grants ID 101390, ID 20045, and ID 125132).

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What is a Causal Risk Factor? (AMA with Alan) Jul 25, 2023

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About this Episode:

We've just released a lengthy 'ask me anything' episode, where Dr. Alan Flanagan addressed specific listener questions, over on the Sigma Nutition Premium feed. In this episode, you'll hear one detailed answer from that AMA, in which Alan discusses the concept of "causal risk factors".

This is a term that is regularly mentioned on the podcast, and has a very specific and important meaning. This episode will give you an in-depth understanding and comfort with the term, which will enhance your future understanding and learning.

If you wish to hear the other 10 questions Alan answered, you can subscribe to Sigma Nutrition Premium here.

#489: Inequalities in Diabetes Outcomes for African & Caribbean Communities – Prof. Louise Goff Jul 18, 2023

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About This Episode:

In the UK, there is a threefold higher incidence of type 2 diabetes in UK African and Caribbean (AfC) communities, compared to the general population. And ethnic inequalities in type 2 diabetes treatment and outcomes have been documented. And so addressing these inequalities is an urgent healthcare priority in the UK.

Differences in outcomes relate to physiological differences as well as pragmatic issues and structural barriers. Professor Louise Goff has done pioneering work in relation to both aspects.

Prof. Goff's research has highlighted ethnic differences in type 2 diabetes pathophysiology between those in UK African and Caribbean groups and white Europeans. This means that typical screening for diabetes may not be as useful for AfC communities, in addition to treatments not being as appropriate.

In addition, there are noted differences in engagement with diabetes education services and self-management advice. This may be due to the fact that the delivery of information is not culturally relevant to those in AfC communities. And so diabetes structured education programs have been found to be less successful in people from minority ethnic groups.

Prof. Goff has attempted to address this by developing a culturally tailored self-management education and support program for type 2 diabetes in black-British adults. This program, called the Healthy Eating and Active Lifestyles for Diabetes (HEAL-D) program, has initially been trialed with local Black African and Caribbean communities and healthcare providers in South London.

In this episode, Prof. Goff discusses the ethnic differences in diabetes pathophysiology and the other factors underlying the inequalities in diabetes outcomes in black African and Caribbean communities.

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#488: Does Time of Day Impact Hunger, Appetite & Satiety? Jul 11, 2023

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About This Episode:

The topic of whether hunger and satiety are affected by the time of day has generated considerable interest within the nutrition research community. Researchers have been particularly intrigued by the potential influence of circadian rhythms on caloric intake throughout the day.

Initially, a number of studies proposed that consuming high energy intakes in the morning could lead to significantly greater weight loss compared to evening consumption. And while much attention was placed on the hypothesis that differences in expenditure were the cause, more recent research has called that into doubt.

And so, it is crucial to consider the possibility that other factors may be contributing to the outcomes observed in the intervention trials. In recent years, a series of papers has suggested an alternative explanation; the impact of time-of-day energy intake on appetite and hunger.

In this episode, Alan and Danny take a look at the current evidence related to this connection between time-of-day, appetite, and energy intake. And then, from that, what does this mean for how calorie distribution may affect dietary intake, body composition and health.

#487: Weight Cutting in Combat Sports – Jordan Sullivan Jul 05, 2023

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"Weight cutting" is a common practice in weight-class based sports. And typically, combat sport athletes have reported cutting the largest amounts of weight for competition.

The concept of cutting weight is based on the assumption that a size advantage gives a performance advantage in combat sports. And by getting into a lower weight class than their "normal" weight, athletes can enjoy an advantage (or, more accurately, not be at a disadvantage).

The decrease in weight from an athlete's habitual weight to their weight-class limit typically has two phases: a chronic weight loss phase (gradual dieting to lose fat mass), and an acute weight loss phase (rapid declines in weight due to losses of water, glycogen and gut residue).

To discuss the science, practical application and dangers of weight cutting strategies, performance dietitian Jordan Sullivan is on the podcast.

Jordan has been the performance dietitian for several years to Israel Adesanya, Alexander Volkanovski, Leon Edwards, Dan Hooker, Kai Kara-France, and many other well-known names.

And he is the co-author, along with Danny, of the new textbook 'Making Weight: The Ultimate Science Based Guide to Cutting Weight for Combat Sports'.

#486: Blood Glucose Spikes: How High is Too High? – Mario Kratz, PhD & Nicola Guess, PhD Jun 27, 2023

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Peaks in blood glucose (or "blood sugar spikes") are commonly highlighted as something harmful to health. And, of course, an excessively high blood glucose response to a meal can be problematic, or at least indicate there is a problem.

However, elevations in blood glucose after eating are a normal physiological response. And "bad" blood glucose responses are those that stay high for a prolonged period; i.e. after elevating, they don't return to normal within an appropriate period of time.

But now many normoglycemic people are worrying about normal blood glucose responses, due to information that portrays even moderate elevations in blood glucose as harfmul. To add to the confusion, people are looking at standardized cut-off thresholds for diabetes and pre-diabetes, and mistakenly using them to label their own response to eating as measured by a continuous glucose monitoring (CGM) device.

When it comes to normoglycemic people, there is still a grey area in relation to how much of a glucose spike is a cause for concern. And given that there are still open questions that evidence has not fully answered yet, there is room for different interpretations of how to answer this question.

So what actually is a blood glucose peak that is "too high"? Is it 7.8 mmol/L (140 mg/dL)? 10.0 mmol/L (180 mg/dL)? 11.1 mmol/L (200 mg/dL)? Or do we even need to think about this once standard measures (e.g. HbA1C) are normal?

To discuss this interesting area, Dr. Mario Kratz and Dr. Nicola Guess are on the podcast to offer some perspectives and their conclusions from the current evidence base.

Blood Glucose Unit Conversions:

1.7 mmol/L = 30 mg/dL
7.0 mmol/L = 126 mg/dL
7.8 mmol/L = 140 mg/dL
9.0 mmol/L = 162 mg/dL
10.0 mmol/L = 180 mg/dL
11.0 mmol/L = 198 mg/dL
11.1 mmol/L = 200 mg/dL

#485: Does Menopause Alter Appetite? Jun 20, 2023

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About This Episode:

Menopause is commonly associated with hormonal changes and physical symptoms, such as hot flashes, mood changes, sleep issues, and weight gain. Based on anecdotal reports, another interesting question emerges: what is the potential impact of menopause on appetite?

As women undergo this transformative phase, many report fluctuations in their food intake and body weight, raising the question: Does menopause alter appetite?

Understanding the relationship between menopause and appetite is of great significance, as it can potentially provide insights into the mechanisms behind weight gain and obesity risk that often accompany this stage of life. Furthermore, comprehending the factors that contribute to changes in appetite during menopause could aid in the development of tailored interventions and strategies to support women's overall health and well-being.

In this episode, we delve into the research to see if we can unearth any answers. What studies have been done? What results do we see? What conclusions does this allow us to make? And what does future research need to do in order to provide better answers?

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