Newsletter #040: Fitness Matters for Long-Term Heart Health, Even Without Chronic Disease Symptoms 🏋️♀️
Welcome to the latest edition of the humanOS newsletter! Here, we’ll share our work, plus some of the cool studies and media that we reviewed this week and that found their way onto our social media channels. 🤓
This Week’s Research Highlights
Researchers performed a meta-analysis of randomized controlled trials that used either CT or MRI to assess changes in visceral adipose tissue in response to either exercise or drugs. A total of 3602 participants from 17 randomized controlled trials were included in the final analysis. They found that exercise interventions resulted in a greater reduction in visceral fat relative to weight loss than did pharmaceutical interventions. As previous studies have shown, exercise doesn't merely burn fat, it ensures that you lose it from the right places.
🍟 We know that excess energy intake from dining out is a likely contributor to obesity - but the much-maligned fast food and chain establishments probably aren’t the only culprits.
Researchers measured energy content of frequently ordered meals in non–chain restaurants in three US locations via bomb calorimetry, and compared that data with the energy content of meals from large-chain restaurants. They found that meals from non-chain restaurants contained on average 1205±465 calories per meal — not statistically different from equivalent meals at large-chain restaurants. American, Italian, and Chinese food had the highest mean energy (1495 kcal/meal), and 92% of meals exceeded typical energy requirements for a single-eating occasion.
Researchers steeped green tea in bottled water, deionized water, and tap water, then analyzed epigallocatechin gallate content via high-performance liquid chromatography. They found that green tea brewed with deionized or bottled water had double the EGCG content, compared to the tea brewed with tap water. It is thought that minerals commonly found in tap water may inhibit extraction of catechins.
Researchers measured cardiorespiratory fitness in 4527 adults who were free of cardiovascular disease or hypertension at the start of the study. After ten years of follow-up, the top 25%, in terms of fitness, had just half the risk of heart attack or angina as the least fit 25%, and the correlation held after adjusting for potential confounders in the most and least fit individuals. For each increase of 3.5 fitness points, the risk of heart attack or angina dropped by 15%.
Podcasts We Loved This Week
- Philip Fernbach: What We Know vs. What We Think We Know. Via Talking Biotech Podcast with Paul Vincelli and Kevin Folta.
- Paul Bloom: Is Empathy Good or Bad? Via Clear + Vivid with Alan Alda.
- Satchin Panda: Circadian Rhythms and Time-restricted Eating to Improve Health and Even Reverse Disease. Via STEM-Talk.
New humanOS Content
- Blog: What Is the Best Time of Day to Exercise to Improve Blood Sugar Levels? By Greg Potter.
Last week, Greg talked about why blood pressure regulation seems to be important for long-term health, and how simply modifying the timing of consumption of different kinds of food can have a surprisingly big impact on blood sugar. We also know, of course, that physical activity plays a key role in how blood sugar fluctuates throughout the day, and there has been a mountain of accumulated research investigating how different exercise modalities and durations contribute to this. But what impact might the timing of physical activity have on blood sugar? Or does it even matter?
Recently, a group of scientists from the Karolinska Institute in Stockholm put this to the test. The researchers recruited eleven men with type 2 diabetes and had them perform two 2-week periods of HIIT while equipped with continuous blood sugar monitors. Both training periods were designed to be identical, with one small difference - in one of the periods, participants performed the HIIT in the morning (8 am) and in the other, they exercised in the afternoon (4 pm). So what happened? Check out the blog to find out!
Media Featuring humanOS
• Dan Pardi: Improving Memory Through Proper Exposure to Light. Via Dr. Ruscio Radio.
The humanOS Bookshelf
How to Read a Paper: The Basics of Evidence-Based Medicine. By Trisha Greenhalgh.
Ginny says: This is a useful introductory text for people who want to learn how to critically interpret scientific papers. The book is largely directed to clinicians but is extremely accessible and easy to understand even for people who are totally new to reading scholarly articles. I would suggest reviewing the guidelines and questions that she presents, and then trying to apply it to an actual peer-reviewed paper (e.g. what was the research design? Was systematic bias avoided or minimized?).