Newsletter #213 - Oat Bran and Heart Health 🫀
Hey, y’all, hope you’re doing all right, wherever you are and whatever you’re up to. This week, I thought we would take a look at a couple of studies examining the effects of oat bran - one of my favorite foods - on cardiovascular risk factors.
So, we have known for decades that oats are linked to lower levels of LDL cholesterol, and thus to reduced risk of cardiovascular disease. Probably not a newsflash for you. A major reason for this association is that oats are an excellent source of beta glucan, a viscous soluble fiber, which seems to be responsible for many of the beneficial effects associated with oatmeal.
Specifically, it is thought that beta glucan interacts with bile acids, preventing their re-adsorption in the ileum and causing them to be excreted. This means that the body has to synthesize more bile acids from cholesterol to replace the losses, which in turn lowers levels of LDL. This is supported by animal and human studies showing higher fecal levels of bile acids following consumption of oats and beta glucans. Beta glucans seem to also alter the composition of the gut microbiota, which could influence cardiovascular health through the production of beneficial metabolites.
Oats are a decent source of beta glucans, but oat bran is better, which is why I chose to zero in on the latter. To put the difference into perspective, one cup of cooked oat bran contains the same quantity of beta-glucan as double the amount of cooked oatmeal, which is probably why oat bran results in greater reductions in LDL than the same amount of oatmeal.
This Week's Research Highlights
🥣 Oat bran lowers atherogenic lipids in healthy young adults.
Researchers recruited 24 young volunteers (age 25.2±2.7 years; BMI: 24.9±2.9), and put them through two 2-week dietary intervention periods. One was a low-fiber control diet, and the other was an otherwise similar diet augmented with 102 grams of oat bran daily. When the researchers compared bloodwork within each participant over the intervention periods, they found that total cholesterol decreased by 14% during the oat bran period, compared with 4% during the control period. Non-high-density lipoprotein (HDL) cholesterol, meaning all atherogenic lipoproteins in the blood, decreased by 16% in the oat bran period compared with 3% in the control period, as did triglycerides (21 vs 10%). The oat bran intervention did not result in significant weight change, which arguably makes this finding even more impressive, since weight loss tends to induce changes in blood lipids independent of the composition of the diet.
💝 Oat bran may increase HDL (good) cholesterol.
Thirty-four premenopausal women were randomly assigned either to a control group (no supplement) or to a treatment group, which received 2 oat bran-enriched muffins per day (28 g/day of oat bran). After four weeks, the women who were supplemented with oat bran experienced an 11.2% increase in plasma HDL-C levels, while the total cholesterol/HDL-C ratio decreased by 7.0%. Worth noting that this is not a consistent finding, with some studies showing no change or even a reduction in HDL, but HDL is also not the biomarker that you want to focus most on in any case.
🩺 Oat bran is linked to lower blood pressure.
Fifty participants with essential hypertension were randomly assigned to either control or to consume oat bran (30 grams per day, containing almost nine grams of dietary fiber). After the oat bran intervention, subjects showed significantly lower blood pressure compared to controls, and their use of antihypertensive drugs was also significantly reduced. This is further supported by a meta-analysis of randomized controlled trials which found that various fiber types were beneficial for blood pressure, but beta glucan specifically resulted in the most significant reductions.
Random Trivia & Weird News
🏆 One man has won both a Nobel Prize and an Ig Nobel Prize.
The Ig Nobel Prize is a satiric prize awarded annually to celebrate ten unusual or trivial achievements in scientific research. The Nobel Prize, well, that one needs no explanation.
Anyway, Andre Geim won an Ig Nobel Prize in 2000, for levitating a frog using its intrinsic magnetism. A decade later, he was awarded the 2010 Nobel Prize in Physics for his work on graphene, and became the first and thus far only person to hold both awards. On the subject of his awards, he said:
"Frankly, I value both my Ig Nobel prize and Nobel prize at the same level, and for me Ig Nobel prize was the manifestation that I can take jokes, a little bit of self-deprecation always helps."
Podcasts We Loved This Week
- Steven Clausnitzer: Freezing stem cells to slow the aging process. Via the LLAMA Podcast.
- Jack Szostak and Betül Kaçar: How could life evolve from cyanide? Via The Joy of Why.
Products We Are Enjoying
Bob’s Red Mill Oat Bran
Oat bran is better than traditional oatmeal in basically every way. It contains more protein, more vitamins and minerals, more antioxidants, fewer calories, and more fiber, particularly beta glucan. Along with its overwhelming nutritional advantages, I personally prefer the texture, and it cooks significantly faster too (a major plus if you are busy and/or impatient).
In order to achieve the threshold of 3 grams of beta glucans, you need to eat about 40 grams of oat bran, so I would recommend consuming that amount (or more) in order to ensure beneficial shifts in your lipid profile. The cool part is that oat bran is actually a really versatile food. It can be prepared in either sweet or savory ways, with fruits or vegetables, or whatever you like, so it’s easy to make it a part of your regular diet.
humanOS Catalog Feature of the Week
Thanks for reading, enjoy the weekend, and we'll see y'all next week!