Newsletter #128: How the Common Cold Might Help Us Fight COVID-19 🤧
Welcome to the latest edition of the humanOS newsletter! We hope everyone is having a delightful and healthy fall (or at least, as much as possible under the circumstances).
This week, we learned that humans may be hard-wired to find and remember calorie-rich foods; near-sightedness may affect circadian rhythms; supplementation with DHA and EPA (from fish oil) may help with pain from osteoarthritis; being male appears to be an independent risk factor for severe COVID-19 due to biological factors; and past infection with coronaviruses that cause the common cold may help train the immune system to fend off COVID-19.
Scroll down for more info, and stay safe everyone. 👇
This Week’s Research Highlights
🍟 Spatial memory in humans appears to implicitly prioritize high-calorie foods.
Researchers created a maze-like setting, in which participants (n = 512) followed a specific fixed path within a room to sample an assortment of high- and low-calorie food stimuli (either eight food samples or eight food-scented cotton pads) at dispersed locations. When participants reached a sample, they either tasted the food or smelled the cotton pad and rated how much they liked it. Participants were then asked to indicate the location of each food or odor sample on a map of the room.
In general, spatial memory was far more accurate when presented with food samples compared to the scented cotton pads. And participants were nearly 30% more accurate at mapping high- than low-calorie foods to the correct location. This suggests, as hypothesized by the authors, that human spatial memory may be biased toward efficiently locating high-calorie foods. This makes sense, as our ancient ancestors evolved in highly complex environments with fluctuating food availability. A high-calorie bias in spatial memory could have optimized foraging efforts, though it may be a liability for us in the modern food environment.
👓 Myopia (near-sightedness) is linked to altered circadian timing.
Researchers recruited 18 participants with myopia and 14 with normal eyesight. They assessed circadian timing through salivary dim light melatonin onset, collected half-hourly for 7 hours, beginning 5 hours before and finishing 2 hours after individual average sleep onset in a sleep laboratory. Total melatonin production was assessed via aMT6s levels from urine collected from 6 pm and until wake-up time the following morning. The researchers found that the subjects with myopia showed a dim light melatonin onset phase-delay of 1 hour 12 minutes compared to those with normal vision. Urinary aMT6s melatonin levels were also significantly lower among myopes (29.17 ± 18.67) than emmetropes (42.51 ± 23.97). Myopes overall had a significant delay in sleep onset, greater sleep onset latency, shorter sleep duration, and exhibited more evening-type diurnal preference than their counterparts with normal eyesight.
💊 Fish oil supplementation may reduce pain from osteoarthritis by enhancing blood flow.
Researchers randomly assigned 152 overweight/obese older participants, most of whom reported chronic pain due to osteoarthritis, to take either fish oil (2000 mg DHA + 400 mg EPA), curcumin, or a combination of both. After sixteen weeks, participants taking the fish oil showed a significant reduction in osteoarthritis-specific pain (curcumin did not reduce pain measures). Reductions in pain in the group taking fish oil was correlated with increases in small artery elasticity index - suggesting that improvements in microvascular function may have played a role in the pain alleviation.
🦠 Recent infection with common cold may reduce severity of COVID-19.
To explore how immune responses to these viruses might affect the response to SARS-CoV-2, researchers examined medical record data from patients who had respiratory panel test results between May 18, 2015, and March 11, 2020. This test detects an array of different respiratory pathogens, including coronaviruses that are linked to the common cold. The researchers also looked at data from people who were tested for SARS-CoV-2 between March 12, 2020, and June 12, 2020. They found that testing positive for a “common cold” coronavirus did not prevent people from being infected with SARS-CoV-2. However, after adjusting for potential confounders, they determined that patients hospitalized with COVID-19 who had had a previous positive test result for another coronavirus had significantly lower odds of being admitted to ICU and had a higher probability of survival. This may be an example of a process known as heterologous immunity. SARS-CoV-2 is a novel pathogen, but it shares genetic sequences with many other types of coronaviruses that have been endemic in humans for a long time, including the etiological agents for the common cold. People with prior experience with other coronaviruses may have primed immune responses that are inadequate to block infection entirely (neutralizing immunity), but it does help prevent severe disease due to COVID-19.
♂️ Being male appears to be an independent risk factor for severe COVID-19.
Researchers in Germany analyzed a dataset from the international multicenter Lean European Open Survey on SARS-CoV-2-Infected Patients (LEOSS) registry. They retrospectively assessed 3129 adult patients with COVID-19, enrolled between March and July 2020. Men predominated this hospital-based cohort in all age groups, and even more so in the age groups >65 years and >75 years. Progression to a critical phase (ICU admission) was seen more often in men than in women (30.6% vs 17.2%), and mortality was significantly higher. Being male was linked to a 62% increased risk of COVID-19-associated death in an analysis adjusted for various factors. Notably, men had significantly higher inflammatory markers (IL-6, CRP, PCT, ferritin) across all phases of disease. Recent studies also suggest that female patients show a more robust T cell activation - which is essential for eliminating the virus - during SARS-CoV-2 infection.
Podcasts We Loved This Week
- Mike T. Nelson: The Flex Diet - A Science-Based Guide to Metabolic Flexibility. Via Nourish Balance Thrive.
- Alan Flanagan: Is Time-restricted Eating Dead? A Closer Look. Via Sigma Nutrition Radio.
- Katherine Wells, James Hamblin, Alex Madrigal: How Bad Will Winter Get? Via Social Distance.
Products We Are Enjoying
Imperfect Foods.
If you are trying to minimize trips to the grocery store due to the resurgence of the coronavirus, but you still want to eat healthy fresh foods, a delivery service might not be a bad idea. Imperfect Foods is a subscription service that sources fresh produce and pantry items that farms and retailers are not able to sell, usually due to cosmetic defects, and ships them to your door in eco-friendly packaging, and at a discount of up to 30% from retail.
Worth noting that the actual quality (and flavor) of the foods that you receive should not be compromised - I’ve never received an item from them that was in really poor condition or couldn’t be eaten.
There are a few different companies that do this, but I think this one is the best because the box is fully customizable. You have the option to receive shipments as frequently or infrequently as you wish, and you can pick every single thing in the box.
humanOS Catalog Feature of the Week
How-to Guide - Chrononutrition (Eating Timing)
This week, we’d like to highlight our how-to guide for chrononutrition. We often fixate on what we are eating, when we are discussing diet and lifestyle, but we are gradually appreciating that when we eat also has a significant impact on our health and our daily performance.
This guide will help show you how to optimize your food timing, in alignment with the latest scientific research, to maintain robust circadian alignment and to ensure you are performing at your very best.
(PS: If you’re looking for a deeper dive into the subject of nutrient timing and other aspects of circadian physiology, please refer to our Circadian OS Program.)