Newsletter #184 - Herbs, Spices, & Hot Peppers 🌿🌶️
Happy weekend, humanOS friends! So, we are pretty much knee-deep into pumpkin spice season. But setting aside this somewhat polarizing spice blend, we became curious about what the research says about dietary intake of culinary herbs and spices - including hot peppers - and health outcomes.
History buffs know that the inexorable desire for spices quite literally changed the world, and not always for the better. Wars were fought over them, and the spice trade was a major driving factor in the Age of Exploration. However, thousands of years before all of that transpired, these plant components were actually valued as a form of medicine. More recently, advances in analytical chemistry have enabled us to precisely identify and quantify various bioactive compounds in edible plants that could be responsible for some of their observed effects. Perhaps unsurprisingly, spices, herbs, and medicinal plants tend to come out on top, boasting the highest concentrations of antioxidants among plant foods. This, of course, makes a ton of sense - it is very likely that the high antioxidant capacity of these plants, among other things, contributed to their apparent medicinal properties.
But it also suggests that they are an underappreciated source of micronutrients and phytochemicals, and probably should be used more, especially since a little can go a long way. One study, for instance, found that incorporating a modest amount of lemon balm into a basic salad doubled the antioxidant capacity of that meal, while adding a similar quantity of marjoram increased it 4-fold. And hotter spices, like chile peppers, may offer some unique benefits of their own, ironically in part due to their characteristic burn.
To learn more about the potential health benefits of herbs, spices, and hot peppers, scroll down!
This Week's Research Highlights
🌶️ Frequent consumption of spicy foods is linked to greater longevity.
Researchers analyzed data from a massive cohort of participants from ten geographically diverse regions across China (n = 199293 men and 288082 women). Subjects reported their frequency of spicy food at baseline, then they were followed for a median of about seven years. After taking into account relevant factors like age, education, family history, exercise, etc, the researchers found that those who ate spicy foods 1-2 days a week had a 10% reduced risk of death, compared with those who ate such meals less than once a week. The risk was 14% lower for those who ate spicy food between 3-7 days a week.
𐄷 Eating chilli peppers is linked to lower risk of obesity.
Researchers in China analyzed data from 12970 adults who were followed over a median of nine years. Dietary data were collected during home visits across the followup period, using 3-day food records. After adjusting for variables like age, smoking, energy intake, and exercise, the researchers found that individuals who ate around 50 grams of chilli peppers day or more had a roughly 25% reduced risk of becoming overweight or obese, compared to those who did not eat peppers. Obviously this does not demonstrate a causal relationship between hot pepper intake and body mass, but there is some biological plausibility here.
Mechanistic studies suggest that capsaicinoids - the chemicals in peppers that are responsible for their characteristic burn - may affect appetite. A systematic review of clinical trials found that administration of these spicy compounds prior to a meal reduced voluntary energy intake in human participants by an average of 74 calories. Obviously that is a fairly modest decrease, but it could certainly add up if sustained long term, ostensibly through regular consumption like we see in observational data.
🩸 Adding spice blends to food can reduce insulin and blood lipids after eating.
Researchers at Penn State recruited six overweight men and had them consume either a control meal or a meal augmented with 14 grams of a culinary spice blend (specifically: black pepper, cinnamon, cloves, garlic powder, ginger, oregano, paprika, rosemary, turmeric - sounds pretty tasty tbh). This was a crossover design, so each participant consumed both meals over the course of the study, with one week between testing sessions. Blood samples before and after the meal revealed that eating the meal with the spices resulted in a 21% reduction in postprandial insulin, and a 31% reduction in postprandial triglycerides, compared to the control meal. Antioxidant activity in the blood was also boosted by about 13%. In another very similar trial, the same research team found that a spice blend also significantly lowered inflammatory markers.
🫑 Adding mixed spices to food may lower blood pressure as well.
Prior research has shown that adding spices to meals may help promote healthy endothelial function after eating, as well as attenuate postprandial lipemia (as shown in the study described above). But do these acute effects necessarily translate into better cardiovascular health over time? To explore this, Penn State researchers recruited 71 people with risk factors for cardiovascular disease and assigned them to an average American diet that only differed in the amount of spices incorporated into them: a low-spice diet (0.5 grams), a moderate-spiced diet (3.3 grams), and a high-spice diet (6.6 grams). Each dietary pattern was consumed for 4 weeks at a time, with a 2-week break between each dietary regimen. Indeed, the researchers found that after consuming the diet with the high dose of spices, participants had lower systolic and diastolic blood pressure. This is fairly impressive since the diets to which these subjects were assigned was not especially healthy (described in the paper, charitably, as “suboptimal”), and demonstrates how a relatively small addition to a diet can improve health in appreciable ways.
Random Trivia & Weird News
🐕 Dogs are renowned for their exquisitely sensitive noses.
But did you know that they may be able to tell time by using their sense of smell?
A scientist who researches dog cognition has theorized that dogs may be able to assess the passage of time through the concentrations of odors. Basically, stronger, fresher scents are likely to be newer, while weaker odors represent things further into the past. This may explain how your dog is able to know when you’re about to come home every day - your scent has faded to a predictable level of faintness, signaling your imminent arrival.
Podcasts We Loved This Week
- Louise Burke: Optimizing big muscle health in athletes. Via the LLAMA Podcast.
- Alan Flanagan & Danny Lennon: Polyphenols and cognitive health. Via Sigma Nutrition Radio.
Products We Are Enjoying
Gochujang fermented chile paste concentrate.
Fantastic hot sauce that you can use on almost anything - I’ve added it to stir-fries, used it as a dipping sauce for vegetables, or even as a sandwich spread.
It’s spicy and tangy (kind of like kimchi), and pretty easy to find at Whole Foods and other grocery stores.
humanOS Catalog Feature of the Week
Thanks for reading, and we will see y'all next week! 🤠