The primary function of starch is to serve as a storage form of energy in plants. Plants produce starch by converting excess glucose molecules generated through photosynthesis into starch, which they store in organelles called amyloplasts. This stored starch can later be broken down to glucose to provide energy for the plant’s metabolic needs, especially during periods without sunlight, such as at night
. For animals and humans, starch is an important dietary carbohydrate that is broken down into glucose by enzymes like amylase found in saliva and the pancreas. This glucose is then used as a vital energy source for bodily functions, including powering the brain and nervous system. Starch provides a more gradual release of energy compared to simple sugars, making it a key fuel source
. Additionally, some starches, known as resistant starches, act like dietary fiber by passing undigested into the colon, where they support beneficial gut bacteria and promote digestive health
. In summary, starch functions mainly as:
- An energy storage molecule in plants
- A dietary carbohydrate that breaks down into glucose for energy in animals and humans
- A source of dietary fiber in the form of resistant starch, supporting gut health
Beyond nutrition, starch also has industrial uses such as thickening agents in food, adhesives in papermaking, and potential bio-battery fuel
