Does Grease Affect Food Digestion?

Eating too much of any one food component can affect your digestion. Grease, in particular, can impact how your body digests a meal because of the specific chemistry of the fats you eat. A high intake of fatty foods may result in indigestion and cause gastrointestinal distress. Seek the advice of a dietitian or your health care provider if your diet, especially one high in fat, causes you digestive problems.


The fats, or lipids, in the foods you eat are predominantly triglycerides of three fatty acids attached to a glycerol. Fatty acids are chains of carbon atoms of varying lengths, with hydrogen atoms bound to the carbons. The structure of the fatty acid determines its chemical characteristics, such as whether it is liquid or solid at room temperature. All fatty acids, however, are insoluble in water. Therefore, food lipids require special treatment in the watery environment of your digestive tract.

Fat Digestion

How Long Until Fat Is Absorbed From Food?

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The fats you eat must be broken down to individual fatty acids and glycerol before the cells of your small intestine can absorb them. The process of fat digestion occurs in your small intestine with the action of the digestive enzyme lipase, produced by your pancreas. However, as a water-soluble molecule, lipase cannot act on the water-insoluble food lipid until it is emulsified, or separated into tiny droplets that can mix with water. A fluid called bile -- produced by your liver and stored in your gallbladder -- is secreted into your small intestine to meet the food lipids, and bile emulsifies the fat so lipase can digest it.


The more grease you eat, the more bile and lipase your body needs to digest your food lipids. If your intake is particularly high, you may overwhelm the capacity of your liver and your pancreas to synthesize sufficient bile and lipase for digestion, and the backlog of fatty foods may result in indigestion. Additionally, the higher the fat content of your food, the more the grease can coat the protein and carbohydrate molecules you eat along with the fatty foods. These normally water-soluble food components might then be rendered essentially water-insoluble until you digest the fats surrounding them. The accumulation of these foods may add to your indigestion.


Lipase & Fat Digestion

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Symptoms of indigestion include abdominal pain, nausea, bloating and an uncomfortably full feeling in your gut. The likelihood of indigestion due to too much grease in a meal is less if you eat slowly and moderate your overall fat intake. Consuming moderate amounts of grease with your meals may also simply slow your digestion without causing the discomfort of indigestion.