I don't know why that's relevant but I'm willing to bet you're referring to a popular science myth about short lifespans
Yes lifespans were extremely short on average in Medieval Europe which faced constant famine and disease from peasants living in such close conditions with animals.
But medieval europe isn't the whole world. Hunter-gather lifespans varied greatly depending on environment but the modal lifespan is usually around 70 years old. Modern archeological evidence shows us that people living past 100 was far from uncommon even 1,000 years ago: