The Fruit and Vegetable Magic Number
First they tell us to eat 3 to 4 servings of fruits and vegetables a day. Then they raised it to 10 servings a day. Oh wait, never mind. It went back to five.
Waffle, waffle, waffle.
But the waffling didn’t stop there. 2017 introduced a “definitive” study that declared the optimum intake of fruits and vegetables to be 375 grams a day and eating amounts larger than that does little good.
Fine, but the definition of a “serving” caused some confusion. According to the World Health Organization (WHO), 375 grams of fruits and vegetables equates to almost 5 servings a day. Okay, but nobody bothered to tell us that the WHO definition of a serving is different from the U.S. definition of a serving.
The WHO says a serving is 80 grams but the U.S. defines a serving as a 125 grams. That problem was compounded by the fact that the average American can only relate to grams as a way to eyeball the approximate amount of weed in a baggie.
Outside of that, grams have little meaning, so when confronted with the veggie/fruit goal of 375 grams, we said screw that metric stuff and just latched onto the goal of eating 5 servings.
Unfortunately, that meant that we poor, gassy Americans were struggling to chomp down almost 600 grams of fruits and vegetables a day while most of the rest of the world was happily munching on a meager 375 grams a day.
Food people, food people! Let’s all get on the same page! Or at least do an American study on fruits and vegetables that uses the American definition of a serving size.
It turns out some Harvard scientists did just that and, lo and behold, they suggest that we Americans were unwittingly on the right track. Five American-size servings is indeed the perfect amount of fruits and vegetables to eat each day. Eating any more than that conveys no additional benefits.
I guess I’m glad we decided on a number, but I think the Harvard researchers and the people that latched onto this study are ignoring a whole bunch of variables. Before we get to that, let’s take a short look at how they came to their conclusion.
What They Did
The Harvard researchers reviewed the health and diets of over 100,000 people ¬– 66,719 women from the much-ballyhooed Nurses’ Health Study, and 42,016 men from the Health Professionals Follow-Up Study – to see how diet affected their health.
They found that the overall risk of up and dying reached its lowest point when study participants had five servings of vegetables a day (two fruit and three vegetables). More surprisingly, they found that eating additional servings didn’t do anything to improve their prospects of living to a ripe old age.
What did matter, though, was the type of fruits and vegetables they ate. “Starchy” vegetables like potatoes and corn didn’t convey many health benefits (to no one’s surprise), but leafy greens, berries, carrots, and citrus fruits did.
Oh, and fruit juices were less healthful than just eating the fruit.
When compared to people who just ate two servings a day (the American average), those who ate five had a 13% lower risk of dying from all causes, a 12% lower risk of death from cardiovascular disease, and a 10% lower risk of dying from cancer.
Not content to consider the matter settled, the researchers then conducted a meta-analysis of 26 other studies involving 2 million people. The results were pretty much similar, although one study found that eating 10 servings a day did offer some additional benefits.
So Is 5 the Magic Number?
What shakes my foundation and makes me all itchy is their conclusion that eating any more than five servings does no damn good.
They’re proposing the number 5 as an immutable barrier, a health “wall” which can’t be breached, no matter how many additional servings of fruit and vegetables are pelted at it.
I felt my foundation stabilizing, though, once I started to think about all the variables that might have influenced that particular finding:
1 Most Americans eat the same damn fruits and vegetables day after day.
As far as vegetables, they eat potatoes and tomatoes and carrots and the occasional salad. Regarding fruits, they eat bananas, apples, strawberries, and oranges.
So eating more servings of the same might not convey additional health benefits because they’re consuming the same vitamins, minerals, and phytochemicals over and over again.
If, however, they introduced more VARIETY into their fruit and vegetable diets – ate things they normally don’t eat – it’s quite plausible they might have experienced even better health.
2 Most Americans eat hybridized or GMO versions of fruits and vegetables.
I don’t believe there’s anything inherently evil about such fare, but most were developed to produce high yield crops that were uniform in size and appearance and had a longer shelf life instead of nutrient density.
If, however, they ate more “heritage” fruits and vegetables (those that were grown from seeds and have been passed down from generation to generation), it’s quite plausible they might have experienced better health because they’ve been found to be more nutritious than those typically sold in grocery stores.
3 The results of the study might have been skewed a bit.
The participants might have only started to eat more fruits and vegetables at the moment their health started to decline, which would reduce the observed effects.
That’s why I have trouble believing that additional servings of fruits and vegetables – as long as they were different fruits and vegetables – wouldn’t convey additional health benefits.
What also bothered me about this study and others like it, though, was that they’re largely dismissive of all the other plant products that undoubtedly improve health just as much as fruits and vegetables. Remember, nutrition isn’t just about vitamins, minerals, and the carotenoids that give plants their vibrant colors – the other plant compounds known as polyphenols ultimately play just as big a role in human health.
Many of them are the basis for supplements you take every day, things like curcumin, resveratrol, cyanidin 3-glucoside, EGCG, and dozens of others, but not all of them are found in fruits and vegetables.
That’s why any study that’s sincere about finding any “magic” formula or equation to human health and longevity needs to take into consideration the other polyphenolic food groupings, things like:
- Whole Grains – Buckwheat, rye, oats, etc.
- Nuts, Seeds, Legumes – Pecans, almonds, etc; flaxseed, sunflower seeds, etc.; lentils, beans, etc.
- Fats – Olive oil, avocado oil, dark chocolate.
- Spices – Rosemary, oregano, cloves, peppermint, anise, saffron, thyme, turmeric, cinnamon, etc.
- Beverages – Coffee, tea, red wine, cocoa.
How many servings of the above did the men and women in any of the studies consume on a daily basis? No one asked and so no one knows.
You Still Didn’t Answer the Question: Is 5 the Magic Number?
Five servings is probably enough to ensure a solid foundation of health, as long as each serving is a different fruit or vegetable.
Furthermore, anyone truly interested in health would rotate the fruits and vegetables in their diet, i.e. introduce new ones on a regular basis.
Would eating more help? Probably, as long as they’re different types and not more of the same. And, even if more servings of fruits and vegetables didn’t help, eating more of them at least means you’re eating them instead of some food that’s processed or non-nutritive, which sure as hell wouldn’t convey any health benefits.
- Dong Wang, et al. “Fruit and Vegetable Intake and Mortality,” Circulation, 2021;143:00-00.