Flavonoids are a group of polyphenols, phytonutrients found in most fruits and vegetables. There are more than 6,000 unique flavonoids, but as a group, they’re most well-known for their antioxidant and anti-inflammatory effects and have been found to lower the risk of many chronic conditions rooted in inflammation. Anthocyanins,¹ specifically — found in red-blue plant pigments that give berries and other foods their red, blue and purple color — have been shown to:

• Improve blood sugar control

• Normalize blood pressure and enhance capillary strength

• Lower oxidative stress and inflammation

• Inhibit platelet formation

• Prevent buildup of arterial plaque

• Increase NAD+ levels

Previous animal studies have shown anthocyanins reduce the production of mucus and inflammatory secretions in animals with chronic obstructive pulmonary disease. Some of the latest research suggests the plant compound can also help slow the gradual decline in lung health associated with aging.

Anthocyanins Protect Lung Health

The study² in question analyzed data from 463 British and Norwegian adults who participated in the second and third European Community Respiratory Health Surveys. The average age was 44. The data included dietary information and a spirometry test, which measures the volume of air you can forcefully exhale in one second (FEV1), the total volume of air you can exhale after taking a deep breath (FVC) and the ratio of the two (FEV1/FVC).

According to lead author Vanessa Garcia Larsen, Ph.D., assistant professor in the Human Nutrition Division of the Department of International Health at the Johns Hopkins Bloomberg School of Public Health, lung function tends to peak around the age of 30, after which it starts to decline.

The rate of speed of that decline varies depending on factors such as smoking, your exercise level, exposure to pollutants and the presence of other medical conditions. Your diet also plays a significant role. Processed foods in general, and processed meats in particular, have previously been linked to a more rapid decline in lung function.³

Here, those in the highest quartile of anthocyanin intake, compared to those in the lowest quartile of intake, had a significantly reduced decline in all three lung function measurements. In the highest quartile of anthocyanin intake, FEV1 declined at an average rate of -9.8 milliliters per year (mL/yr) compared to -18.9 mL/yr for those in the bottom quartile of anthocyanin intake. FVC declined at a rate of -9.8 mL/yr compared to -22.2 mL/yr.

On average, the annual decline of FEV1/FVC among those consuming the highest amounts of anthocyanins was just -0.02 per year. No association between anthocyanin intake and lung function was found among smokers, however. According to Garcia-Larsen:⁴

“Our study suggests that the general population could benefit from consuming more fruits rich in these flavonoids like berries, particularly those who have given up smoking or have never smoked. For smokers, quitting remains the best thing they can do to protect their health.”

Flavonoid-Rich Diet Has Many Other Health Benefits as Well

Aside from protecting your lung function with age, polyphenols — the plant compounds that give fruits, vegetables and berries their vibrant colors — have numerous other health benefits as well. This includes lowering your risk of “middle-age spread,” the weight gain around the midsection that is so common with age.

In one study,⁵ which included more than 124,000 people, those with the highest flavonoid intake had the least weight gain with age. Certain types of flavonoids were more effective for weight maintenance than others, particularly after the researchers accounted for fiber intake. Anthocyanins, proanthocyanidins and total flavonoid polymers (found in tea and apples) showed the most significant effect after adjusting for fiber.

Overall, for each standard deviation above average in terms of flavonoid consumption, the study participants gained one-tenth to three-fifths of a pound less over four years. This might not sound striking, but you can consider it the icing on the cake, as this is just one of many benefits. Other health benefits associated with higher intake of flavonoids include:

Reduced risk of diabetes6

Improved blood pressure7

Lower risk of heart disease8 Six classes of flavonoids were identified as having a significant impact on heart disease risk, namely flavonols, anthocyanidins, proanthocyanidins, flavones, flavanones and flavan-3-ols

Lower risk of erectile dysfunction among men9

Improved memory consolidation, learning and overall brain function10 The flavonoid responsible for this effect was apigenin, found in many herbs, including parsley, thyme and chamomile. Cocoa flavonoids are also associated with both cardiovascular and brain benefits. In one study,11 those who ate dark chocolate at least once a week had better mental performance than those who did not, and previous research12 has found epicatechin in dark chocolate also helps protect your brain after a stroke by increasing cellular signals that shield nerve cells from damage. Further, when diabetic patients were given a special high-flavonol cocoa drink for one month, it brought their blood vessel function from severely impaired to normal.13 The improvement was actually as large as has been observed with exercise and many common diabetic medications.

Cancer protection14 When mice implanted with cells of a particularly deadly, fast-growing human breast cancer were treated with the flavonoid apigenin, the cancerous growth slowed and the tumors shrank. Apigenin may even be one reason why drinking chamomile tea has been found to reduce thyroid cancer risk by up to 80 percent.15 Interestingly, the compound was also found to bind to 160 proteins in the human body, which suggests it has far-reaching health effects. Additionally, treatment of cells with apigenin or quercetin inhibits CD38 and promotes an increase in intracellular NAD+ levels.16 CD38 is the primary enzyme that lowers NAD+ levels, so by inhibiting it, NAD+ levels are increased. Onions and garlic are also rich in flavonoids, including quercetin, which inhibits the growth of cancer cells. Unlike anthocyanins, which had no effect on lung function in smokers, quercetin17 has been shown to reduce the risk of lung cancer in smokers. It also reduces your risk of heart disease, lowers blood pressure, relieves symptoms of interstitial cystitis and reduces symptoms of prostatitis.

Bone health18 In fact, flavonoids have been said to have “the most potential of dietary components for promotion of bone healthy beyond calcium and vitamin D,” and research suggests they have a stronger association with bone health than even general fruit and vegetable consumption.19