Feel like crap after that Ben and Jerry's? Or constantly feel like you shouldn't have had that latte? You're not alone. Up to 75 per cent of the world's population is in some way intolerant to dairy products, leading to somewhat undesirable reactions involving your gut or even skin.
It's notable that proportionally more people of Asian and African descent than other races have this unfortunate intolerance, due to the lack of dairy in their diet while developing.
This common intolerance to dairy products is usually due to one of two things; an allergy to milk proteins, or an inability to properly digest a sugar that is present in dairy called lactose – a condition known as lactose intolerance. An incredible 15 per cent of the UK's population suffers from the latter condition, people I affectionately refer to as "lactards." Not a huge amount can be done to avoid the deathly consequences of Ben and Jerry's Peanut Butter Me Up if you're allergic to milk proteins except avoidance, but if you're lactose intolerant there's a really simple treatment available: You can supplement your body's resources of lactase.
The reason one in seven of you can't drink milk is a lack of this enzyme, normally produced in the cells that line your small intestine. And when there's not enough lactase to process the lactose you ingest, your body can't process the lactose into simpler forms of sugar that your body can absorb easily, and your body goes nuts, because you've just eaten something your stomach can't digest. Hello discomfort.
Logistically, if your body is lacking something, what would your next step be? Oh I don't know, maybe supplement it? Here's where the miraculous solution comes in -- it's available in most health food shops, including Holland and Barretts (Useful to know when they have one of their sales), and Amazon. The food industry has jumped on this recently; you can buy lactose free (mostly) products from most supermarkets. They're simply dairy products with added lactase -- genius.
This is a very well documented 'treatment' for lactose-intolerance, but unfortunately not very well publicised by a large amount of clinical nutritionists and GPs, and as a result, there are a huge amount of unnecessary toilet trips are going on out there. So, if you feel like crap after having that glass of milk, you can likely make it stop by popping a pill.
There's a large train of thought that we as humans are not supposed to be ingesting dairy in the first place, and in reality, it's a little odd for a fully grown mammal to be drinking the milk of another species. It doesn't happen a lot in nature, but in reality, the nutrients found in dairy are largely no different to the nutrients you can find in other foods -- when you break it down enough, protein is protein, and calcium is calcium. The trick is training your body to do that effectively, and providing it with the necessary tools to do so.