The real burying of the lede here is within the first few sentences:

> Consuming two liters of diet soda [...] a day can increase the risk of a dangerous irregular heartbeat by 20% [...]

Much in the same way of the hysteria around soy causing gynecomastia, it happens when you consume absurd amounts of the stuff.

I found that odd in the article as well. I wonder if there are any drinks other than water of which you could drink two litres a day without any ill-effects to your health.

Green tea maybe?

How is that absurd amount?

2 litres of (diet) soda is definitely an absurd amount

2 liters of soda everyday is huge. If it was sometimes (in a party, etc) it would be fine, but I can't imagine drinking close to that amount everyday.

I am sure that people do even worse, but at that point you're in a bad situation if you drink normal (e.g.: the amount of sugar) or diet soda.

Daily recommend fluid intake for men is 3.7 liters (20% from food).

2l of something doesn't seem excessive.

2L of what is essentially a dessert liquid is very much absurd.

We're not talking about water.

2L of pretty much anything that isn't water is very likely too much.

Put it this way: go read up experiences on reddit of people doing the GOMAD diet.

The article is wrong. The study actually says two liters _per week_ increases risk of irregular heartbeat. 2L/week is much less absurd of an amount: it’s slightly less than 1 can per day.

Just because an explanation is satisfying to speculate about doesn't make it correct

I agree. Moralistic people want diet soda to have some sort of downside due to a feeling that they worked hard to lose/maintain their weight and therefore so should everybody else. The problem is every experimental study finds diet soda is really zero calorie and without any major downsides, it's only the observational studies that are flawed in the way I described that ever find these sort of "effects".

Such sweeteners are everywhere, for example in many sports drinks and sports supplements.