Newsletter #156: Garlic, Beetroot, and Crucifers 🥦
Welcome to the first day of May, and to another humanOS newsletter! On the research front, this week was mostly focused around specific vegetables and their impact on long-term health and especially on the cardiovascular system.
We discovered how nitrates from veggies improve vascular health; that cruciferous vegetables may lower risk of pancreatic cancer (one of the worst forms of cancer you can get), and raw garlic might slow down the development of atherosclerosis.
Finally, on the not-so-good side, we were reminded once again why dining out frequently is generally not the best thing for your health.
To find out more more, scroll down 👇🏼
Media Featuring humanOS
Dan Pardi: How to Optimize Health. Via VatorNews Podcast.
This week, Dan also had the opportunity to chat about the evolution of healthcare with Bambi Francisco Roizen on the VatorNews Podcast. On this show, he talks about how we define health, the many dimensions of health (which are often overlooked), and how our approach to healthcare could be improved. Check it out!
This Week’s Research Highlights
🍟 Dining out frequently is associated with increased risk of death from any cause.
Researchers examined interview responses and long-term health outcome data from participants in NHANES 1999-2014 (n=35084). Subjects reported dietary habits, including frequency of eating meals prepared away from home. After adjusting for various confounders, the scientists found that people who frequently ate food prepared away from home had 49% higher risk of all-cause mortality, 67% higher risk of cancer mortality, and 18% higher risk of cardiovascular mortality (compared to those who seldom ate meals prepared away from home). Not super surprising - we know that home cooking tends to be linked to better diet quality (and it is likely to be less expensive too, which is a nice bonus).
🥬 Consumption of nitrates from vegetables is associated with lower cardiovascular risk.
Researchers analyzed dietary data, blood pressure readings, and cardiovascular outcomes from participants in a large Danish cohort (n=53150), who were followed for 23 years. Over the course of the study, participants who consumed a moderate amount of nitrates from vegetables (median of 59 mg per day) experienced a 15% lower risk of cardiovascular disease, compared to those in the lowest category of intake. Specifically, moderate vegetable nitrate intake was linked to 12%, 15%, 17% and 26% lower risk of ischemic heart disease, heart failure, ischemic stroke, and peripheral artery disease hospitalizations respectively. This association appeared to be mediated in large part by reductions in blood pressure, which makes sense since nitrate augments nitric oxide, which in turn relaxes the walls of the blood vessels.
🫀 Drinking beetroot juice may promote good vascular health by altering the oral microbiome.
Okay, here's some more good stuff on vegetable nitrates. Researchers at the University of Exeter had 26 older adults go through two 10-day intervention periods - one in which they consumed nitrate-rich beetroot juice twice a day, and another in which they drank a nitrate-free placebo beverage. After the beetroot juice intervention, the researchers identified significant shifts in the composition of the oral microbiome of the participants. Subjects showed higher levels of bacteria associated with better vascular function and cognitive health, and lower levels of bacteria associated with disease. These microbial changes were accompanied with increased systemic nitric oxide bioavailability, elevated plasma concentrations of nitrate and nitrite, and an average drop in systolic blood pressure of 5 mmHg. To learn more about the benefits of beetroot juice, check out our interview with Jonathan Burdette from Wake Forest, who has done some exceptional research on this very subject.
🥦 Consuming cruciferous vegetables - especially raw - is linked to lower risk of pancreatic cancer.
Researchers analyzed and compared data from 183 pancreatic cancer patients and 732 cancer-free controls. After adjusting for various potential confounders, they determined that subjects consuming >1.5 servings per week of raw cruciferous vegetables had 40% lower odds of having pancreatic cancer, compared to those consuming less than 0.5 servings per week. Furthermore, each additional serving per week was associated with 7–15% lower odds of pancreatic cancer. Importantly, strongest associations were seen for raw veggies, which may be a clue to underlying mechanisms. Cruciferous vegetables are rich sources of compounds called glucosinolates. These compounds exert a variety of biological activities - including detoxification of cancer-causing agents - but they appear to be sensitive to heat.
🧄 Eating raw garlic is inversely associated with carotid intima-media thickness, an early marker of atherosclerosis.
Researchers analyzed data from participants in a cohort study in Tianjin, China (n=4329). During their health examinations, these participants received a carotid intima-media thickness test (cIMT), test that measures the thickness of the inner two layers of the carotid artery, and is used to identify plaque buildup in the walls of these arteries before patients are symptomatic.
Participants also provided data on their dietary habits, including their consumption of raw garlic. The researchers found that people who ate raw garlic 1-3 times weekly experienced a 26-29% reduction in risk of thickened cIMT, compared to infrequent consumption. Underlying mechanisms are not clear, however a number of trials using garlic supplements have found that garlic can significantly lower blood pressure and reduce accumulation of soft plaque in arteries.
Podcasts We Loved This Week
- Peter Hotez: Evolution of the anti-vaccine movement, the causes of autism, and COVID-19 vaccine state of affairs. Via The Drive with Peter Attia.
- Alan Flanagan: Irritable bowel syndrome (IBS) and diet. Via Sigma Nutrition Radio.
Products We Are Enjoying
Kyolic Aged Garlic Extract
If you are not a garlic enthusiast, another way to reap some of the benefits is to take a supplement. One form that has been commonly studied is Kyolic aged garlic extract. One meta-analysis found that garlic supplements lowered systolic and diastolic blood pressure by an average of 8.3 mmHg and 5.5 mmHg respectively, and that Kyolic aged garlic specifically lowered central blood pressure, arterial stiffness, and boosted the richness and diversity of the gut microbiota.
