A Big Mac weighs 215g but has only 25g of protein. Add the french fries and coke and you basically have a whole bunch of carbs and fat.

Even their ice creams don't contain much protein. A large McFlurry with Oreo's is 381g but has only 15g of protein (and 85g of sugar).

source: http://nutrition.mcdonalds.com/getnutrition/nutritionfacts.p...

There's an amino acid called glutamate which creates an umami or "meaty" flavor. It's present in various additives such as monosodium glutamate and hydrolyzed yeast extract. Look at the nutrition facts of e.g. Doritos or Cheez-Its; you'll likely find one of these additives.

Wouldn't that be something with an umami taste?

That makes sense to me, but when I think of cultures that are big on umami I don't see a lot of obesity, so I'm not sure if the point connects fully.

I used to believe that the Japanese diet is inherently healthier because there is lower obesity in Japan. I've asked Japanese people about this and they say that it's actually quite a struggle for many of them to not gain weight, but they work hard to keep their weight down because that's what's expected of them to fit in.

So now my theory is that lower Japanese obesity is more a result of a strong sense of cultural conformity rather than something inherently healthy about the diet.