If your fart smells bad, here's what your body is warning you about and the foods to cut ASAP
ETimes November 24, 2025 12:39 PM
If your fart smells bad more often than usual, it is usually your gut hinting that something in your diet is not being digested smoothly. While occasional strong odour is normal after a heavy or sulphur-rich meal, persistent or unusually foul-smelling farts often reflect what is happening deeper in the digestive system. Odour usually forms when bacteria ferment food that the body struggles to break down. This can happen because of food choices, intolerance, gut imbalance or simple eating habits. The good news is that once you identify the cause, a few simple swaps can reduce the smell dramatically. In some cases, your body may even be signalling an early sensitivity that is worth understanding.
A peer-reviewed scoping review published on examined the sulphur content of common foods and how these compounds are metabolised in the human gut. The researchers found that sulphur-rich foods lead to the formation of volatile sulphur compounds such as hydrogen sulphide, which are the main drivers of strong-smelling farts. Read the study here:/ The findings clearly explain why certain meals produce stronger odour and why shifting to lower sulphur choices can noticeably reduce smell.
What bad-smelling farts actually mean for your body
When your fart smells bad frequently, your body might be pointing toward one of these issues:
Excess sulphur in your diet
Sulphur is healthy in small amounts but produces foul smelling gases when broken down by gut bacteria.
Gut bacteria imbalance
When odour producing bacteria dominate, fermentation becomes stronger and the smell becomes more noticeable.
Mild food intolerance
Lactose, gluten, garlic, onions and high FODMAP foods can produce pungent farts when poorly digested.
Fat malabsorption
If your body struggles to break down fat, it can lead to oily, foul smelling farts.
Eating too fast
Swallowing excess air and sending half chewed food to the gut increases fermentation.
The foods most likely to make your fart smell stronger
High sulphur foods naturally create stronger odours. These include:
• Eggs
• Red meat
• Garlic
• Onions
• Broccoli
• Cauliflower
• Cabbage
• Brussels sprouts
• Certain seafood
• Beans and lentils
When these foods reach the colon, bacteria break down their sulphur content into hydrogen sulphide and similar gases. This is normal but can lead to a stronger odour if eaten in large amounts or if your gut is sensitive.
How gut imbalance can make your fart smell worse
Your gut microbiome plays a major role in how your digestion smells. Antibiotics, stress, low fibre diets or too many processed foods can shift the balance of bacteria. When odour-producing bacteria take over, even mild foods can result in unpleasant-smelling farts. Signs of imbalance often include bloating, irregular bowel movements and fatigue. Increasing fibre, probiotics and hydration can help restore equilibrium.
Foods to cut back on if your fart smells bad
These foods are the most common contributors:
Eggs
High in sulphur and can cause very strong odour. Swap with chickpeas or tofu occasionally.
Red meat
Dense and harder to break down. Try choosing chicken or fish more often.
Garlic and onions
High sulphur and high FODMAP. Replace with herbs like parsley or coriander if needed.
Cruciferous vegetables
Nutritious but odour-producing. Rotate instead of eating large amounts in one meal.
Dairy
If lactose-intolerant, the smell becomes extremely strong. Try lactose-free versions.
Fried or high-fat foods
Difficult to digest and can create strong odours through fat malabsorption.
Artificial sweeteners
Sorbitol and maltitol ferment heavily and produce strong-smelling farts.
Simple fixes that reduce bad-smelling farts fast
Small changes can significantly reduce the smell:
• Drink more water to help digestion
• Add yoghurt or kefir for probiotics
• Eat slowly and chew properly
• Spread sulphur foods throughout the day
• Choose more soluble fibre, like oats and bananas
• Replace fizzy drinks with water or herbal teas
• Avoid lying down immediately after meals
Most people notice improvement within a few days.
When bad-smelling farts are worth paying attention to
Smelly farts are normally harmless and simply reflect your digestion. However, if the odour becomes very strong suddenly or is accompanied by weight loss, diarrhoea, abdominal pain or fatty stools, it may indicate an underlying issue worth checking. Conditions such as lactose intolerance, coeliac disease, irritable bowel syndrome or problems with fat absorption can create unusually foul-smelling farts. A quick evaluation helps rule out anything serious.
If your fart smells bad, it usually means your diet or digestion needs a small adjustment, not that something is seriously wrong. Understanding which foods trigger stronger odours and making simple swaps can keep your gut comfortable and reduce embarrassing moments. For most people, the solution is straightforward: support your gut, tweak your food choices and listen to what your body is gently warning you about.
Disclaimer: This article is for general informational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider regarding any medical condition or lifestyle change.
Also read|
