Europeans were lactose intolerant for 4,000 years
New research has revealed that ancient Europeans adapted the ability to digest dairy much later than expected. It's long been known that after humans transitioned from hunter gatherers to farmers, many populations also evolved the ability to tolerate lactose, a sugar found in dairy. But new DNA evidence now shows that this ability evolved much later in certain populations - and for 4,000 years ancient Europeans were eating cheese, despite not being able to stomach it.
Scientists had estimated that lactose tolerance must have evolved around 7,000 years ago or more, when cheese-making first started. But the researchers found that the genes didn't actually appear until 3,000 years ago. The next step is to map the distribution of the lactose-tolerant gene further, and find out more about how our genetics changed in response to our diet.
This seems to show that human evolution doesn't happen as quickly as expected, and lends some credence to the saying: Starving people have no food allergies.
Scientists had estimated that lactose tolerance must have evolved around 7,000 years ago or more, when cheese-making first started. But the researchers found that the genes didn't actually appear until 3,000 years ago. The next step is to map the distribution of the lactose-tolerant gene further, and find out more about how our genetics changed in response to our diet.
This seems to show that human evolution doesn't happen as quickly as expected, and lends some credence to the saying: Starving people have no food allergies.
This is only a possibility. This does not exclude, that many people never have a severe reaction. And it does not exclude that even if such a risk of a severe reaction does exist, it is so rare that it does not prevent the allergic persons to pass on their genes... An opportunity these persons might never have had, if they rather starved than accepted the risk.
Btw.. a friend of mine is allergic to flavour enhancers. Not really a big deal. He gets some minor skin problems. From time to time he says (more or less): "F**k it... today I want to eat my ". I doubt he would do it, if doing so he constantly would had the sword of Damocles of a deadly reaction over his head.
I looked for some statistics, but did not have much time. So this must be enough:
http://www.medicinenet.com/script/main/art.asp?articlekey=15618I would interpret this that two-thirds never have fatal or near-fatal reactions.