International Numbering System (INS) for Food Additives: 270
Food additives Europe numbers: E270
Lactic acid is a type of acid found in animal and plant tissues and fluids. It is produced naturally in the body and is an important part of the energy cycle in cells. It is also used in medicine to treat a variety of conditions, including lactic acidosis, digestive problems, and certain skin disorders. Lactic acid is available in various forms, such as topical creams, oral tablets, and intravenous solutions. It has been studied for its potential benefits in a range of conditions, including exercise performance, fatigue, and pain management.
Lactic acid is a fascinating substance that plays two important roles in the body:
1. Fuel for Cellular Energy:
- Lactic acid is an organic acid produced naturally in your body during cellular respiration, the process by which cells convert glucose (sugar) into energy [1, 2].
- It's particularly abundant in muscles that rely heavily on anaerobic respiration (without oxygen) for short bursts of energy, like during intense exercise [2].
2. Building Block and Signaling Molecule:
- Beyond being a byproduct of energy production, lactic acid also serves other purposes [2, 3]:
- Building Block: Lactic acid plays a role in the production of glucose through a process called the Cori cycle. In this cycle, lactate produced in muscles is transported to the liver and converted back into glucose for use as fuel by other cells.
- Signaling Molecule: Lactic acid can act as a cellular signaling molecule, communicating information between cells. For instance, it can signal muscle fatigue during exercise.
Lactic Acid and Muscle Soreness:
A common misconception is that lactic acid buildup directly causes muscle soreness after exercise. While lactic acid does accumulate during strenuous activity, research suggests it's not the primary culprit for soreness [4]. Muscle soreness is likely due to microscopic tears and inflammation caused by exercise.
Medical Uses of Lactic Acid:
- Lactic acid also has some medical applications [5]:
- Food Additive: Lactic acid is used as a food additive due to its preservative properties and its ability to add a tangy flavor. It's found in yogurt, pickles, and some sour candies.
- Skin Care: Lactic acid, as a type of alpha hydroxy acid (AHA), is used in some skincare products to exfoliate dead skin cells and promote smoother skin.
Important to Remember:
- Lactic acid is a normal part of human metabolism and shouldn't be a cause for concern under usual circumstances.
- However, very strenuous exercise or certain medical conditions can lead to a buildup of lactic acid in the blood, causing a condition called lactic acidosis. This is a serious medical condition that requires immediate medical attention.