Flavonoids are having their moment
Nutrient found in fruits, vegetables is tied to having multiple health benefits including better blood pressure
Dear Doctor: What are flavonoids? All of a sudden, they’re in the news, and it sounds like if you get enough of them, you’ll have normal blood pressure. Can you get them in regular food?
Dear Reader: Flavonoids are definitely having a moment, and not for the first time. Two new studies join a larger body of existing research that associates flavonoids with a wide range of health benefits. They exhibit anti-inflammatory, antiviral and antitumor properties, which have been associated with a reduced risk of certain chronic diseases, including cancer, cardiovascular disease and neurodegenerative disorders.
As you have noticed, one of the two newer studies links the consumption of flavonoidrich foods to improved blood pressure. The results of a separate study tie the nutrients to a lower incidence of cognitive decline in older adults. It’s important to note that these are observational studies. That means that, while the data points to certain conclusions, the methodology isn’t able to prove cause and effect.
Let’s start with flavonoids themselves. They are chemical compounds that, in addition to giving fruits and vegetables their bright colors, are directly involved in the development and growth of plants. They’re also referred to as phytonutrients. These are chemical compounds that plants produce that, while often beneficial to humans, are not essential to maintain life. The primary dietary sources of flavonoids are fruits, vegetables, some herbs, tea, wine and dark chocolate. Citrus fruits, blueberries, blackberries, cherries, red cabbage, kale, onions, apples, pears, peppers, oregano and parsley are excellent sources.
Flavonoids, which are broken down by the trillions of microbes that live in our gut, are subdivided into six groups. These are based on their chemical structure. Each subgroup offers unique health benefits, which makes it important to eat from a wide and varied range of fresh fruit and vegetables.
In the study that you heard about, which was published in Hypertension, a journal of the American Heart Association, researchers in Northern Ireland analyzed one year of health and dietary data from 900 study participants. They also sequenced the genetic composition of the bacteria in their guts. They found that consuming foods rich in flavonoids influenced the composition of the gut microbiome in a way that was beneficial to blood pressure. The effect appeared to be especially pronounced in people who ate at least 1 1/2 servings per day of foods rich in the subcategory of flavonoids associated with blue- and red-colored foods, such as blueberries, blackberries and red grapes.
In the other study, which appears online in the journal Neurology, researchers at Harvard University analyzed 20 years of health and nutritional data collected from 100,000 women and men. They found that people who ate a diet abundant in flavonoids lowered their risk of cognitive decline by as much as 20%. In this study, scientists said they suspect that the antioxidant properties of flavonoids have a protective effect on the blood supply to the brain.
There’s no specific recommendation for the quantity of flavonoids someone should eat each day. Instead, the takeaway here is to make a wide array of fresh fruits, vegetables and leafy greens a centerpiece of your diet.
Dear Doctor: I’m a 74-year-old male with a stubborn case of jock itch. I’ve tried every over-thecounter ointment, powder and soap, with no success. A prescription cream keeps it from getting worse, but it doesn’t stop the problem. Do you have
any other recommendations on how to treat this?
Dear Reader: Jock itch is a topical infection that can be caused by keratinloving fungi known as dermatophytes, and by a yeast known as candida. Also known as tinea cruris, jock itch is a red, scaly and very itchy rash that appears in areas of the body that stay warm and moist. It gets its name because it’s common in athletes, and also from its location in the area of the groin and inner thighs. It’s more common in men than in women, and it can also arise in people who perspire freely, individuals who are overweight and people with a weakened immune system.
The battle against jock itch takes place on two fronts. One is the use of antifungal medications. This includes the drug store creams, lotions, soaps and powders that you have tried, and a small number of prescription medications. Most people do have success with over-the-counter treatments. More persistent cases of jock itch can call for a prescription for topical medications, including oxiconazole or econazole, or an oral medication, such as fluconazole or itraconazole. If you haven’t had success with topicals, ask
your health care provider if an oral treatment might be the next step.
It’s important to understand that medications are only a start. Just as important is eliminating the environment that allows fungi to flourish. That means a thorough and sustained campaign to keep the affected areas very clean and very dry. And by sustained, we mean remaining vigilant from now on. Meds can ease a fungal infection in the short term, but you now know you’re susceptible to this type of condition. That means keeping the affected areas clean and dry will become part of your daily routine. If not, recurrences of the condition are likely.
We recommend that our patients who are dealing with jock itch also use a barrier method, like Butt Paste or Desitin, which are zinc oxide-based creams. Something else that has proved effective, particularly in humid climates where getting completely dry is a challenge, is using a blow dryer. Put it on the lowest heat setting so you don’t risk burning yourself, and use it to remove all residual moisture. That, along with the barrier cream, will eliminate the environment that fungi crave. You’ll also want to start wearing loose-fitting
clothing, including underwear, to allow maximum air flow. And be vigilant about washing your hands, which can transfer the fungi. Also, be aware that it can take a month, or even longer, to vanquish a case of jock itch.
If your condition persists despite meds and proper hygiene, you may not actually have jock itch. Other conditions, such as lichens planus, can present with similar symptoms. We recommend that you seek out a board-certified dermatologist to make sure
you’ve received an accurate diagnosis.
Eve Glazier, M.D., MBA, is an internist and associate professor of medicine at UCLA Health. Elizabeth Ko, M.D., is an internist and assistant professor of medicine at UCLA Health. Send your questions to askthedoctors@mednet. ucla.edu, or write: Ask the Doctors, c/o UCLA Health Sciences Media Relations, 10880 Wilshire Blvd., Suite 1450, Los Angeles, CA, 90024. Owing to the volume of mail, personal replies cannot be provided.