It's embarrassing when you have excess wind, even more so when it's particularly smelly. Why does it effect some people more than others?

There are foods that are more complex for your digestive system to break down and are therefore more likely to cause wind. As my kids point out 'beans, beans good for your heart, the more you eat the more you fart!' Other specific foods like onions and artichokes contain a substance that our gut bacteria feed off and this can produce a little wind too. The same can happen when you start taking probiotics if they contain FOS.

However, if you are struggling  with regular bouts of smelly wind chances are something's not quite right with your digestion. There might be a specific food or food groups that are an issue for you. For many this is dairy and people often assume that it is due to lactose intolerance – an inability to break down the lactose in milk due to a missing enzyme. Lactose intolerance can indeed can cause wind. Although you might have this problem, quite often there is an intolerance to the protein in the milk too. If milk protein, usually casein, is a problem then lacto-free milk won't make the symptoms go away completely.

Testing for food intolerances is a good first step to figuring out the cause of your wind. Another factor that causes smelly wind is low stomach acid. If this is the case then you will probably struggle to isolate one group of foods that cause the problem. This is because any protein dense food can be a trigger. Stomach acid breaks down protein, if you don't produce enough then partially digested food travels through the digestive system and the gut bacteria will feed off it and this produces lots of wind. 

Factors affecting stomach acid levels include zinc deficiency, stress and antacid or proton pump inhibitor (PPI) use. Correecting digestion from the stomach through to the gut flora is the best way to erradicate excess wind.