Even though undernourished older women have more of the hunger hormone in their blood, they still don’t eat more—so high hunger signals don’t always make people eat.

Older women who aren't eating enough feel less hungry than younger women, even though their bodies are making more of the hunger hormone, which might explain why they eat less as they age.

Women with more of the hunger hormone ghrelin tend to burn fewer calories at rest and after eating, even when you account for their body size and insulin levels.

Older people don’t feel hungry after eating because their body doesn’t release the right hunger hormone the way younger people do.

Women with more ghrelin — the hunger hormone — actually eat less each day, which seems surprising but was observed in this group.

Even though hunger and fullness hormones are different in older women, those differences don’t match up with who eats less—so the problem probably isn’t the hormones themselves.