It’s an interesting question 
From your nick I’d venture to guess that you are a man, so we’ll set aside the possible hormone fluctuations during the month.
Life-style matters and being more physically active can make a difference.
But, I’d like to ask you about the quality of food you are eating in Switzerland.
It sounds counter-intuitive, but it’s not.
People living in less developed areas may have produce of a better quality.
I moved to the West almost 20 years ago and my digestive problems have started about then.
In my country, which is no longer the case, we hadn’t had a highly industrialized food industry.
If you live in a city and do your shopping in supermarkets even green-markets, you are most likely to buy produce that has been treated with pesticides, hormones… not to mention that it is not ripe when harvested or even sufficiently mature when slaughtered.Even the type of grain matters, when it comes to cereals and vegetables.
He are some of the things I noticed:
-I cannot digest garlic from China;
-the type of wheat you are most likely to find in all the breads you buy (even if you buy them in chic bakeries!) does not come from old varieties and it is richer in starch and gluten (not to mention that these days gluten itself is added to baked goods to make them look fresh for longer periods of time);
-
highly processed dairy products (and I live in France!) - first of all the milk comes from huge dairy farms where cows are pumped with all sorts of antibiotics (ruining your gut bacteria balance) and hormones, then they process it in the way that saves them money - they add powdered milk to yogurt (even in organic ones!);
-
meat and eggs… hormones, antibiotics… I started getting flatulent from beef, my hormones went wild from poultry…
So, a couple of years ago we started spending more time in the country (in the regional park, where no pesticides or hormone treatments are allowed, where cattle grazes and moves freely on the pastures…) and we discovered a wonderful world of local producers, who first and foremost produce food for themselves! I reintroduced certain types of food I avoided like plague in the city (meat, dairy, bread…)
No more flatulence from meat and cereals!
Dairy stopped giving me hormonal problems…
The question is, can we afford to eat good quality food (less processed with no additives), especially if we are living in cities?
In France, it is almost impossible. Even if you do your shopping in organic stores.
You would really need to have enough resources (money and time) to go to farms and buy directly from producers. But it’s really complicated…
I didn’t want to make this post this loooong…
Hope it helps 