As we have seen in this investigation already, passing stools is a much more complicated topic than simply daily routines we do typically after a large meal. If you have frequent bowel movements, clear mucous in your stools, are currently have a period or have a change in the shape, size or color of your normal stools, that could be enough for doctors to try to investigate a bit further to determine if there is an underlying pathology . Another reason that patients could be alarmed could be due to a change in the smell of their stools. Foul-smelling stools are a common concern in the general population and there are numerous reasons why this could be happening. Here, I will focus on some of the more common causes of foul-smelling stools and what you can do about it.
Foul-smelling stools seem to become the norm in Western civilization due to the types of foods that we typically eat in North America. Foods heavy in fat and grease can lead to changes in our intestinal mucosa. It is hard for our bacteria to be able to process and cope with this heavy diet and as a result, our stools will have a foul-smelling odor. 
These fatty diets can also impact the quality of the pancreas. The pancreas is an organ that many people can identify and could have some type of pathology if they drink too much, but you should know what else this vital organ can do. Not only is pancreas an organ that can regulate the amount of sugar in your blood during a meal but it is also the key to help your body process fats. When we eat fatty meals, the pancreas secretes specialized enzymes called lipase, amylase, and trypsin. Lipase and amylase are both keys in the digestion of fats while trypsin is helpful when you are digesting proteins . At normal quantities of food, our pancreas can keep up with the load of fats and proteins that we need to digest. However, when we eat large portions of fats and proteins, the concentration of digestive enzymes are not sufficient enough to fully process the food that we just ate and as a result, and our stools become more concentrated with fats. The reason proteins are not as likely in our stools is because they are absorbed in the intestinal tract as well as in the kidneys so we can process them much more effectively. 
These fatty stools will not only be foul-smelling, but they will also be very "greasy" in appearance and will most likely float to the top of the toilet bowl. If you generally eat a plant-rich diet, you may be able to easily remember a situation where a greasy meal at a fast food diner leads to you having digestive pains. Those who are more likely to eat in these "greasy spoons" may not have the astute observation because their bodies are more likely to process the foods. Their stools will still be quite smelly, however.
Not only will overworking your pancreas lead to foul-smelling stools, but damage to the pancreas can also prevent it from working entirely. Pancreatitis occurs when a person consumes typically excessive amounts of alcohol. The alcohol will cause inflammation in the pancreas and the patient will experience a cascade of typical symptoms.
Abdominal pain will surely ensue, followed by a bout of frequent bowel movements and finally, you will find you have foul-smelling stools. What you can do about this is to manage your drinking habits to reduce your chance of developing pancreatitis. There are some other possible causes like gallstones that can lead to pancreatic inflammation or severe abdominal trauma, but it is much less common than binge drinking. 
Inflammatory Bowel Conditions
The last disease cascade that I will cover is the root of numerous causes of foul-smelling stools. Various conditions such as Celiac disease, Crohn disease, Ulcerative colitis, inflammatory bowel syndrome, or lactose intolerance can all lead to foul-smelling stools. The underlying mechanism that is similar in all these conditions is the irregularity of bacteria along the intestinal tract. When bacteria are not able to help digest and process what you intake, it will result in foul-smelling stools.
If you find that you are suffering from long-term conditions such as chronic, watery diarrhea and foul-smelling stools, you need to go for a consultation with a gastrologist. After a colonoscopy and biopsy, the extent of the condition will be better known, and appropriate antibiotic therapy can begin. 
These are just a few of the many causes of foul-smelling stools and what you can do about it. If you find you have any of these symptoms, try dietary changes at first and consult with a gastrologist to get to the bottom of it.