Hello and welcome to Nutrition Facts. I’m your host, Dr. Michael Greger. Today, we’re going to explore smart nutrition choices based, naturally, on facts. Have a history of high blood pressure in your family? How about heart disease? Diabetes? There are foods we can eat that may not only help prevent many of these chronic diseases but even stop them in their tracks.
Most of us are familiar with the Standard American Diet – hamburgers, hot dogs – French fries – chips – soda; the list goes on. Research has found that this diet may be so detrimental to blood flow within our arteries, that sexual dysfunction, heart attacks, and strokes can be the result. Industrial pollutants such as PCBs, found mostly in fish, may contribute to sexual dysfunction, impotence and the loss of libido. The regular eating of calorie-dense junk may down-regulate dopamine receptors and result in a reduced neurological capacity to enjoy all the pleasures in life.
With all that bad news here, are there some positive steps we can take? Selecting foods to improve pelvic blood flow and decrease inflammation both long-term and immediately after a meal may improve sexual functioning in men and women. Here’s the story.
What are some “[p]ill-free ways to improve your sex life”? “Exercise,…quit smoking,” don’t drink too much, don’t weigh too much, and “[e]at a healthy diet.” But, what does that mean? “[H]eart-healthy lifestyle changes” are sex-healthy lifestyle changes—as has been demonstrated in studies from around the world, including in women. “Sexual function in women is [also] significantly affected by [coronary artery disease],” atherosclerotic narrowing of blood flow through our arteries, including the arteries that supply our pelvis. So, high cholesterol may mean “lower arousal, orgasm, lubrication, and satisfaction,” and the same with high blood pressure.
So, putting women on a more plant-based diet may help with sexual functioning. Researchers found that improvements in Female Sexual Function Index scores were related to “an increased…intake of fruit, vegetables, nuts and [beans],” and a shift from animal to plant sources of fat. And, the same with men: a significant improvement in international Index of Erectile Function scores.
In fact, the largest study on diet and erectile dysfunction found that “each additional daily serving of fruit[s or] vegetable[s]” may reduce the risk by 10%. But, why? It may be due to the anti-inflammatory effects. Two years on a healthier diet resulted in “a significant reduction [in] systemic inflammation, as indicated by…reduced levels of C[-reactive protein].” Fiber itself may play an “anti-inflammatory role…” Those who eat the most fiber tend to have significantly lower levels of inflammation in their bodies. The opposite was found for saturated fat, associated with an “increased likelihood of elevated C[-reactive protein]” levels.
People don’t realize that the level of inflammation in our bodies can change after a single meal. For example, there’s a pro-inflammatory signaling molecule in our bodies called interleukin-18, thought to play a role in destabilizing atherosclerotic plaques. As such, the level of “Interleukin-18 [in the blood] is a Strong Predictor of Cardiovascular Death…”
What would happen if you fed people one of three different types of meals: sausage and egg-butter-oil sandwiches, or cheese-less pizza with a white flour crust, or the same cheese-less pizza, but with a whole wheat crust? Within hours of eating the sausage sandwich, interleukin-18 levels shot up about 20%—an effect not seen eating the plant-based pizza. And, those eating the whole food, plant-based pizza had about a 20% drop in IL-18 levels within hours—reinforcing dietary recommendations to eat a diet “high in fiber and [starches], and low in saturated fat, to prevent chronic diseases.”
But, the billions are in pills, not plants, which is why “[t]he pharmacology of the…female orgasm” is studied ever since 1972, when a researcher at Tulane University implanted tubes deep within the brain of a woman, so he could inject drugs directly into her brain, and was able to induce “repetitive orgasms.” A man who had electrodes placed into similar parts of his brain was given a device for a few hours that allowed him to press the button himself to stimulate the electrode. He pressed the button up to “1,500 times.”
Vegetables such as beets and arugula can improve athletic performance by improving oxygen delivery and utilization. But what about for those who really need it—those with emphysema, high blood pressure, and peripheral artery disease?
It’s great that we can improve athletic performance eating a few beets, but so what if you run 5% faster? It can be a fun experiment to eat a can of beets and maybe shave a minute off your 5K time, but these are the people who could really benefit from a more efficient use of oxygen: those suffering from emphysema. Yeah, young healthy adults eating greens and beets can swim, run, and cycle faster and farther, but what about those who get out of breath just walking up the stairs? Do nitrate-rich vegetables work where it counts? Yes, significantly extended time on the treadmill after two shots of beet juice.
It’s great that beet juice can decrease blood pressures in young healthy adults, but what about those who really need it: older, overweight subjects? Just one shot of beet juice a day versus berry juice as a control, and in a few weeks, a significant drop in blood pressure; but within just a few days after stopping—after three weeks of beet-ing themselves up—blood pressures went back up. So, we have to eat our vegetables, and keep eating our vegetables.
Why did it take until 2015 to publish a study on lowering blood pressure in people with high blood pressure? You’d think that’d be the first group to try it on. Who’s going to fund it, though—Big Beet? Blood pressure medications rake in more than $10 billion a year. You can’t make billions on beets. But that’s why we have charities like the British Heart Foundation, which funded a study to give folks with high blood pressure a cup of beet juice a day for four weeks. After all, high blood pressure may be the #1 risk factor for premature death in the world. In ten years, it could affect nearly one in three adults on this planet. But put them on beet juice, and blood pressures dropped and kept dropping, until it was stopped after a month. With so many people with high blood pressure, even despite treatment, an additional strategy, based on the intake of nitrate-rich vegetables, may prove to be both cost-effective, affordable, and favorable for a public health approach to hypertension.
What about those with peripheral artery disease? Tens of millions with atherosclerotic clogs impairing blood flow to their legs, which can cause a cramping pain in the calves, called claudication, due to lack of blood flow through the blocked arteries, severely limiting one’s ability even to just walk around. But just drink some beet juice and walk 18% longer.
The nitric oxide from vegetable nitrates not only improves oxygen efficiency, but also oxygen delivery by vasodilating blood vessels, opening up arteries so there’s more blood flow. I’m surprised beet juice companies aren’t trying to position themselves as veggie Viagra; it could certainly explain why those eating more veggies have such improved sexual function, though this study was just a snapshot in time. So, you can’t tell which came first. However, it seems more reasonable that low fruit and vegetable consumption contributes to erectile dysfunction, rather than the other way around.
What about the most important organ, the brain? Poor cerebral perfusion—lack of blood flow and oxygen in the brain—is associated with cognitive decline and dementia, and they showed that the nitrate in vegetables may be beneficial in treating age-related cognitive decline. They showed a direct effect of dietary nitrate on cerebral blood flow within the frontal lobes, the areas particularly compromised by aging. This is a critical brain area for so-called executive function, basic tasks, and problem-solving important for day-to-day functioning. The nitrite from nitrate has been shown to not just increase blood flow to certain areas of the body, but also acts preferentially in low-oxygen conditions, allowing it to increase blood flow precisely in the areas where it is needed the most. And, that’s what they found in the brain: increased blood flow to the at-risk areas of the aging brain. And, the only side effects of beet-ing your brains out? A little extra color in your life.
When done right, love may protect your lover’s life.
“Sex is important to health,” according to the Harvard Health Letter. “Frequent sexual intercourse is [evidently] associated with reduced heart attack risk.” But, this seems to me the perfect case for reverse causation. They’re implying that more sex leads to healthier arteries. But, isn’t the opposite more likely—that healthier arteries lead to more sex? Blood flow in the penis is so reflective of blood flow elsewhere that penile Doppler ultrasound can predict cardiovascular disease. But, “low frequency of sexual activity [may predict cardiovascular disease in men] independently of [erectile dysfunction]”—suggesting that sex may be more than “just fun,” but therapeutic. Or, at least, so says an editor of the Journal of Sexual Medicine, in discussing whether or not “frequent sexual activity [should] be prescribed…to improve…general…health.” In men, they suggest, it’s because more sex means more testosterone.
When men make love, they get a big spike in testosterone levels in their blood. But, interestingly, in contrast, they get no testosterone boost when they masturbate. This may be because “[t]estosterone increases with competitive success,” like if you win at a game of sports. While sex “is not usually regarded as a competitive event,…one’s mental state [afterwards] could nevertheless be something like that of a winner,” as opposed to the mental state after masturbation.
The spike in sex hormones in the blood is so great that men’s beards actually grow faster on days they have sex. And, since low testosterone levels are associated with “increased risk of mortality,” that could help explain the health benefits.
So, do men who have more sex actually live longer? I did a PubMed search for sexual activity and longevity, and came up with “Sexual Activity and Longevity of the Southern Green Stink Bug.” Our taxpayer dollars, hard at work. But, I was less interested in whether or not screwworms live up to their namesake, and more interested in this: “Sex and Death.” A study whose objective was “to examine the relation between frequency of orgasm and mortality.” They found that men “with high orgasmic frequency” appeared to cut their risk of premature death in half. And, apparently, the more the better—a 36% drop in mortality odds for every additional “100 orgasms [a] year.”
“Conclusion: Sexual activity seems to have a protective effect on men’s health.” But not, it appears, if you cheat. “Unfaithfulness in men seems to be associated with a higher risk of major cardiovascular events,” like heart attacks and strokes. “Extramarital sex may be hazardous and stressful, because the lover [may be] younger” and more exuberant, and “secret sexual encounter[s]” may be more stressful.
In a large autopsy series, the majority of cases of sudden death during sex occurred in men having extramarital intercourse. The absolute risk is low; “only one out of 580 men might be expected to suffer” such a death. But, for those at high risk, “[s]ex in familiar surroundings, [at] a comfortable room temperature, and with [one’s] usual partner” may be safer.
And, speaking of safe sex, you thought drinking and driving was bad? “While [it’s] generally assumed that sexual behavior happens in parked cars, there is little discussion…in the research literature of sexual activity in moving vehicles.” About one in five college students report engaging in sex “while driving”—nearly half while going more than 60 miles an hour, including feats likely involving “distraction.” Researchers suggest maybe this is something that should be warned about in health class.
When done right, though, love may protect your lover’s life. Given the benefits of sexual activity, “[i]ntervention programmes could…be considered, perhaps based on the…’At least five-a-day’ campaign aimed at increasing fruit and vegetable consumption—although the numerical imperative may have to be adjusted.”
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Thanks for listening to Nutrition Facts. I’m Dr. Michael Greger.
This is an approximation of the audio content, contributed by Allyson Burnett.