Saving the planet, protecting animals, and living longer have not shifted enough people. Scientists have found another possible reason to eat more plants: vanity.
Eating more fruit and vegetables could make you look more attractive, smell better and potentially help you achieve your desired body shape. Yes, really.
A scientific review has pulled together more than 30 studies looking at the relationship between food and physical attractiveness. And while it absolutely does not prove that every vegan is hotter than every meat-eater, the evidence suggests that what you put on your plate can change how other people perceive you. Sometimes within weeks.
Researchers David Goldman and Matthew Nagra looked at 3 major ingredients of human attractiveness: our faces, our body odour and our body composition.
The face evidence is particularly striking.
Fruit and vegetables contain carotenoids, the natural yellow, orange and red pigments found in foods such as carrots, tomatoes and leafy greens.
When we eat them, those pigments can accumulate in our skin. And apparently humans are into that. In experiments where researchers altered photographs of faces, people repeatedly preferred skin with stronger carotenoid colouring.
In one series of studies, carotenoid-enhanced faces beat the alternatives in 75.9% of comparisons. Researchers have also watched people’s skin actually change after they started eating more fruit and vegetables.
One six-week study found that increased consumption changed both skin yellowness and redness. Researchers calculated that eating around 2.9 extra portions of fruit and vegetables per day was enough to make people look healthier. Around 3.3 extra portions was enough to produce a change judged more attractive.
In other words, your mother telling you to eat your vegetables may have undersold the benefits.
Then we get to sweat.
In one controlled experiment, 17 men ate either a meat-rich diet or a non-meat diet for 2 weeks. Women then smelled samples of their armpit odour.
The sweat produced while the men were eating the non-meat diet was rated as more attractive, more pleasant and less intense. Another study found that men whose diets were associated with higher fruit and vegetable intake produced sweat described as more floral, fruity and sweet. Lower fruit and vegetable intake was associated with smells described as animal-like, meaty and oily.
And then there is garlic. Garlic is treated as the food most likely to destroy your chances of romance. It may deserve an apology. Experiments found that men eating larger amounts of garlic produced body odour that women rated as more attractive, more pleasant and less intense. Researchers suggested garlic’s antioxidant and antibacterial properties might alter the compounds and microbes responsible for body odour.
There is, admittedly, a limit to how confidently we can declare garlic an aphrodisiac for your armpits. The evidence comes from one publication containing 3 experiments, and the review authors themselves say more research is needed.
Then comes body shape.
Plant-based eating patterns have been associated with lower BMI and greater reductions in body fat compared with omnivorous diets, while separate research has found that body fat influences attractiveness ratings.
But this is where we need a cold shower.
Nobody has yet shown directly that switching to a plant-based diet changes someone’s body composition and therefore causes other people to rate them as more attractive. The researchers themselves call that connection indirect. And some attractiveness findings are downright uncomfortable. Research cited in the review found that the body-fat level rated most attractive for women could fall below the physiologically healthy range. So turning this into “lose weight and become hotter” would not just be scientifically sloppy. It could be harmful.
The researchers instead think the more interesting opportunity lies in visible changes such as skin glow up.
Because public health has a problem.
“Eat more vegetables because it might reduce your disease risk in 30 years” is sensible advice. It is not necessarily exciting advice.
“Eat more vegetables and you might look better in a few weeks” has rather more immediate appeal to our short term brains. And there is evidence that vanity works. In one randomised trial, people shown personalised images of how eating more fruit and vegetables could change their appearance significantly increased their intake for 10 weeks.
People given ordinary information did not. Another study involving 802 people found that 57% were motivated after seeing a demonstration of diet-related skin colour changes.
This research mostly concerns plant-forward diets, meaning diets rich in plant foods that may still contain some animal products. It is also a narrative review rather than a systematic review, and the authors acknowledge a risk that the studies selected could favour their hypothesis. But the basic finding is difficult to ignore. Eat more plants and your skin can change. Your smell can change. People may notice.
Perhaps vegetables just needed the marketing budget that animal flesh has.