What Happens to Your Body When You Eat Enough Fruits & Vegetables
The nutrition world is fraught with controversy about what is and isn't good for you, but there is one thing most everyone can agree on: we should all be eating more fruits and vegetables. And you don't have to be a mathematician to know the advice about eating five servings of fruits and veggies a day. Or do you?
Researchers discovered that eating 400 grams of fruits and vegetables each day could help prevent chronic illnesses like cancer, heart disease, stroke, and dementia. They translated that into five servings a day, which became the predominant public health message for decades. Today, the message has been simplified even more to "fill half your plate" with produce, thanks to the USDA's MyPlate guidance. Despite the catchy slogan, only about 10% of Americans meet their needs on a typical day.
"The message hasn't really changed, as much as the USDA determined that it's easier for people to relate to a plate visually," says Taylor Wallace, Ph.D., the chief food and nutrition scientist for the Produce for Better Health Foundation. The magic number is still five a day. But today, USDA guidelines recommend cups instead of servings, and the precise number is a function of your individual nutritional needs. For most people, that's about 2 cups of fruits and 3 cups of vegetables.
What Happens to Your Body When You Eat Enough Fruits & Vegetables
While half of your plate might not seem that ambitious, most people are not getting enough produce in a typical day. But there can be some serious benefits to upping your intake. Here's what the science says you can expect if you hit the magic number of around five servings per day.
You may have a lower risk of heart disease
"The strongest evidence for the benefits of fruits and vegetables is regarding the prevention of cardiovascular disease," says Wallace. Produce is so helpful that an International Journal of Epidemiology study found that people who ate about six servings (or 18 ounces) of fruits and veggies a day were 16% less likely to die from coronary heart disease than people who ate less than 1½ ounces daily.
One big reason is that the soluble fiber in produce can help block the reabsorption of cholesterol from the intestine and can help lower blood cholesterol levels, explains study co-author Edward Giovannucci, M.D., M.P.H., a professor of nutrition and epidemiology at the Harvard T.H. Chan School of Public Health. (Top sources of soluble fiber include apples, Brussels sprouts, sweet potatoes, pears, oranges, peas and grapefruits). Fiber also slows glucose absorption, a bonus for your heart and your blood sugar. "When sugars are rapidly absorbed in the intestine, blood glucose rises, quickly leading to a rapid increase in insulin," says Giovannucci. "Over time, high levels of insulin and glucose can contribute to diabetes, and can also damage blood vessels, leading to heart disease."
The heart-forward benefits of produce aren't just about fiber. Bell peppers, citrus, kiwis, broccoli, strawberries and others deliver vitamin C, an antioxidant that controls artery-damaging inflammation. Vitamin C also boosts nitric oxide, a gas that relaxes the arteries for better blood flow. It's so helpful that research reveals people who consume a vitamin C-heavy diet may be 21% less likely to die from cardiovascular disease than those who eat little of this nutrient.
You may have a reduced stroke risk
The World Health Organization estimates that feasting on 7½ servings of produce a day might reduce the risk of stroke by anywhere from 10% to 19%. This is in part thanks to potassium. Produce provides more of this blood pressure-lowering mineral than any other food group. And high blood pressure is a leading risk factor for stroke.
But isn't high blood pressure all about sodium? Actually, that's only part of the picture. When you eat, say, a salty pickle, its sodium pulls water into your cells, increasing the pressure in your blood vessels. On the other hand, potassium coaxes water out of cells, lowering blood pressure. "Interestingly, studies show that people who have both very high potassium and very high sodium intakes don't have a problem with hypertension because these electrolytes are in balance," says Wallace. Considering fruits and veg like potatoes, bananas and avocados help deliver the potassium our bodies need and are naturally low in sodium, they're a slam-dunk for stroke prevention.
Your brain health might improve
Whether your goal is emotional well-being now or warding off dementia later, colorful produce can be a helpful ally. A 2020 Nutrients systematic review concluded that consuming five or more daily servings is linked to better mental health, particularly less depression. While any produce was a win, citrus, bananas, berries, apples, kiwis, cucumbers, carrots, lettuce, tomatoes and leafy greens like spinach provided the best brain-supporting benefits. Researchers can't say exactly why produce is a boon for your brain, but they note nutrients that are plentiful in produce, like B vitamins, vitamin C, carotenoids, polyphenols and fiber-rich carbs, are linked to better brain function.
If longer-term brain health is on your mind, flavonoids can help (get them from oranges, berries, apples, pears, peppers and celery). This family of plant compounds is believed to guard against memory loss and dementia by increasing blood flow to the brain, suppressing inflammation and shielding brain cells from harmful beta-amyloid plaques that lead to Alzheimer's disease. For example, a 2021 Neurology study reported that adults who downed the most flavonoids were 19% less likely to experience the early stages of age-related memory loss than those who ate few flavonoids. And if you're an OJ drinker, good news: Volunteers consuming the most flavones, a type of flavonoid abundant in oranges and orange juice, trimmed three to four years off their brain age.
You may be protected from certain cancers
Wallace shared that 1 in 5 cancers is linked to unhealthy diet and lifestyle habits, which include low intake of fruits and vegetables. How does produce fit in? "In very large epidemiologic studies, where people provide detailed information about everything they eat and drink, the rates of developing some cancers are lower in people who eat a diet high in fruits and vegetables," says Anne McTiernan, M.D., Ph.D., a professor of epidemiology at the Fred Hutchinson Cancer Research Center. Why only "some" cancers? "Certain cancers are so rare that they don't show up enough to study," explains McTiernan. "Or they may be so strongly associated with another cause that it's difficult to see the effects of vegetables and fruits [like cervical cancer and the HPV virus]."
The strongest evidence, according to the National Cancer Institute, is for cancers of the mouth, esophagus, stomach, colon, breast and lungs. For the best defense, they recommend up to 6½ cups of produce a day. But they don't stop there. They call out specific colors and types, namely orange, dark green and cruciferous veg for their carotenoids and glucosinolates, phytochemicals that shield cells from carcinogens and guard against DNA damage.
These colorful veggies are also a powerful weapon against breast cancer. In one recent study, women who loaded up on four weekly servings of yellow-orange and cruciferous vegetables (especially winter squash, broccoli, cabbage and cauliflower) were 17% less likely to develop breast cancer than those who ate these vegetables just twice a week.
You might have easier healthy weight management
Keeping off unwanted weight is as much about what you eat as what you don't. In one study, participants who reported eating nine servings of produce a day were 74% less likely to gain weight over a decade than those who consumed half that amount. The secret ingredient? The volume of fruits and veg that comes from water. Flavorful as produce is, it's roughly 90% H20. "Water provides lots of volume and weight, but no calories," says Barbara Rolls, Ph.D., director of the Laboratory for the Study of Human Behavior at Penn State University, who was not affiliated with the study. "This allows you to eat larger, more satisfying portions for relatively few calories."
However, it's not just about water. As anyone who's ever tried to wolf down a salad can attest, fiber-filled fruits and vegetables take time to chew, especially if they're raw. In addition to giving your mouth a workout, fiber also slows down the rate that food empties from your stomach, explains Rolls, allowing your brain extra processing time to register that you're full. Perhaps that's why research reveals loading up on fruits and nonstarchy vegetables can be as effective as a calorie-restricted diet for modest weight loss.
You may live longer
No pill can come close to the cocktail of vitamins, minerals, fiber and 5,000-plus bioactive compounds that fruits and vegetables offer. No wonder they might help you live longer, says a recent study that tracked the eating habits of 108,735 people for three decades. Those who downed two servings of fruit and three servings of nonstarchy vegetables daily enjoyed the greatest longevity, reducing their odds of early death from conditions like cancer, cardiovascular disease and respiratory disease by 13% compared to people who only ate two produce servings a day.
Today, most of us still aren't following the advice to eat our fruits and veggies, but there are some compelling reasons to up your intake. Whether it's through adding them to things you already eat, keeping canned or frozen versions at-the-ready or adding a side of salad or fruit to your meals, strive to eat five (or more) servings of produce each day.