Are vegan diets a bad idea for older people?

The objection

“Old people are losing muscle as it is. Putting a pensioner on a vegan diet is asking for frailty and falls.”

The answer

This deserves a serious answer, because ageing genuinely changes the maths, and dismissing the concern would be dishonest.

Two things happen with age. Muscle responds less readily to protein, so older people actually need more protein per kilogram than younger adults, not less. And appetites shrink. Stack those against the fact that plant foods are less protein-dense and you get the real risk the objection is gesturing at: a simulation study found a large share of older adults on a vegan pattern fell below estimated protein requirements, partly because hitting the target means eating more food than a small appetite wants.

So the concern is legitimate. But notice what it actually indicts. The culprit is inadequate protein and low appetite, which plants happen to make likelier without being the cause. And the controlled-trial evidence keeps the door wide open. The same 2024 meta-analysis found no difference in strength or physical performance between plant and animal protein, and soy matched dairy for muscle mass. Where the deficit shows up, it’s a shortfall of quantity and density, both of them addressable.

What addresses it: build meals around protein-dense plants, soy (tofu, tempeh, soya milk), seitan, lentils, with protein powder if appetite is poor, spread protein across the day, and pair it with resistance exercise, which is the single biggest lever against age-related muscle loss on any diet.

The defensible position: a vegan diet in later life is viable but demands deliberate, protein-forward planning, which is exactly the planning frail older adults need regardless of diet. The risk is undereating protein. The fix is enough of the right plants and lifting something heavy, and meat is nowhere on that list.