We’re often told the importance of eating fruits and vegetables, with little detail as to why they’re beneficial.
Keep reading to learn how fruits and vegetables might help you feel freaking awesome to a ripe old age.
What are fruits and vegetables?
The meanings of the words “fruit” and “vegetable” might vary, based on who you ask, but “fruit” typically refers to the reproductive parts of plants – think seed-containing foods like apples, berries, or even avocados and olives – while “vegetable” typically refers to the non-reproductive parts of plants – think leaves, stems, and roots like broccoli, spinach, celery, or carrots (1).
What are the health benefits of fruits and vegetables?
Higher fruit and vegetable consumption is associated with reduced risk of cancer (mouth, pharynx, larynx, nasopharyngeal, renal cell, lung, colorectal, liver, non-Hodgkin lymphoma, pancreatic, and hepatocellular carcinoma), coronary heart disease, cardiovascular disease, depression, diabetes, hypertension, metabolic syndrome, hip fracture, stroke, ulcerative colitis, wheeze prevalence, asthma severity and prevalence, Crohn’s disease, Barrett’s esophagus, and cognitive disorders (2).
Experimental studies show why this may be the case, demonstrating fruit and vegetable consumption to promote several beneficial effects in the human body, including (3):
- Antioxidant activity
- Modulation of detoxification enzymes
- Stimulation of the immune system
- Decrease in platelet aggregation
- Alteration in cholesterol metabolism
- Modulation of steroid hormone concentrations and hormone metabolism
- Blood pressure reduction
- Antibacterial and antiviral activity
The health benefits of fruits and vegetables are thought to be driven by their concentrations of dietary fiber, vitamins, minerals, and phytochemicals, including carotenoids, flavonoids, and polyphenols (4).
Do fruits and vegetables help you lose weight?
Fruits and vegetables are often recommended for weight loss, and there is evidence that they promote satiety and help reduce energy intake, at least in the short term (5).
There’s also observational data suggesting an association between increased fruit and vegetable consumption and weight loss (6), and some experimental data suggesting fruits and vegetables might play a causal role in weight loss (7).
However, at least two meta-analyses of randomized controlled trials – considered more powerful evidence (8) – suggest that eating more fruits and vegetables has minimal to no effect on weight, energy intake, or body composition (9, 10).
Which fruits and vegetables should you eat?
You’ll probably want to focus on more nutrient-dense fruits and vegetables, those that offer the highest concentrations of beneficial nutrients per serving and/or calorie.
There is no standard measure of nutrient density, but one classification, “Powerhouse Fruits and Vegetables”, is based on concentrations of potassium, fiber, protein, calcium, iron, thiamin, riboflavin, niacin, folate, zinc, and vitamins A, B6, B12, C, D, E, and K (11).
The Powerhouse Fruits and Vegetables include cruciferous and green, leafy vegetables – watercress, Chinese cabbage, collard green, kale, arugula, chard, beet green, spinach, chicory, and leaf lettuce – and citrus fruits and berries – strawberry, orange, lime, grapefruit, and blackberry.
Raspberry, tangerine, cranberry, garlic, onion, and blueberry were also considered for Powerhouse Fruit and Vegetable classification due to evidence of their health benefits, but didn’t make the final cut.
Some folks with health conditions like gastrointestinal or autoimmune disease have benefited from excluding certain fruits and vegetables with low-FODMAP diets (12), low- to no-fiber diets (13), or an autoimmune protocol (14,15,16).
How much variety of fruits and vegetables should you eat?
Other research, however, suggests that the total amount, but not variety, of fruits and vegetables in one’s diet might be what reduces disease risk (19).
That said, eating a wider variety of fruits and vegetables might be an effective strategy for eating a greater amount of fruits and vegetables (20).
How many fruits and vegetables should you eat each day?
It’s generally recommended to eat more fruits and vegetables, but there may be a point at which eating more won’t necessarily help.
One large meta-analysis of 95 studies concluded that 600 – 800 grams (approx. 1.5 – 2.0 lbs.) of fruits and vegetables per day is the point at which the benefits of eating more start to plateau (21).
This is around eight to ten servings per day.
Another smaller, but more recent, meta-analysis of 26 studies concluded that only 400 grams (approx. 1.0 lb.) – 160 g. of fruit and 240 g. of vegetables, specifically – per day might be the point of diminishing returns (22).
This would be around five servings – two of fruit and three of vegetables – per day.
If those amounts sound like a lot, consider starting with one more serving per day than you’re eating now.
Don’t forget to explore and experiment to find an approach that works for you.
Seek out fruits and vegetables that you enjoy (copious added salt and fat can help).
Pay attention to how different types and quantities of fruits and vegetables make you feel.
You might prefer more fruit and fewer vegetables, or vice versa.
You might prefer a lot of both or none of either.
Only you can determine what’s best for you.
Start where you are.
Do what you can.
One step at a time.
You’ve got this.