What is Propylene glycol?
Propylene glycol (PG) is an organic compound with the chemical formula C3H8O2. It is a clear, colourless, and viscous liquid that is nearly odourless but possesses a slightly sweet taste [1].
Propylene glycol's chemical structure consists of a propane backbone (three carbon atoms) with two hydroxyl groups (-OH) attached to the first and second carbon atoms. This configuration makes it a diol, a type of alcohol with two hydroxyl groups [1].
Uses of Propylene glycol
Moisturizer in skin care products: Propylene glycol acts as a humectant, drawing moisture into the skin. It is used in many lotions, creams, and serums to improve hydration. [2]
Solvent and penetration enhancer: Propylene glycol helps active ingredients penetrate the skin more effectively. This property makes it worthwhile in serums and treatment products [2]
Preservative: Propylene glycol has antimicrobial properties that help prevent the growth of bacteria and extend the shelf life of cosmetic products. [2]
Emulsifier and stabilizer: In cosmetic formulations, propylene glycol helps mix ingredients that usually wouldn't blend, like oil and water. It also stabilizes products. [3]
Food additive: Propylene glycol is used as an emulsifier, anti-caking agent, and
texturizer in food products. [4]
Pharmaceutical solvent: Many oral, topical and intravenous medications use propylene glycol as a solvent and carrier for active ingredients. [5, 6]
Industrial uses: Propylene glycol makes polyester compounds, coolants, antifreeze, plasticizers, heat transfer and hydraulic fluids. [2]
Is Propylene glycol in food safe?
Propylene glycol is generally considered safe for consumption in moderate amounts [4, 7]. The U.S. Food and Drug Administration has approved its use in food, and it is often regarded as a relatively safe alcohol compared to others like methanol and ethylene glycol [7]. However, high doses or prolonged exposure can lead to toxicity, especially in individuals with renal or hepatic insufficiency.
Despite these potential risks, it's important to remember that the likelihood of experiencing these effects is generally low, especially when propylene glycol is consumed in moderate amounts as part of a regular diet. Some experts suggest that the acceptable daily intake could be increased from 25 to 62.5 mg/kg bw-day, applicable to children and adults [8].
In conclusion, while propylene glycol is generally safe for consumption in food, it's essential to consume it in moderation to avoid potential side effects. As always, it's best to consult with a healthcare professional if you have specific health concerns or dietary restrictions.
Avoiding propylene glycol in foods
- Read ingredient labels
- Limit ultra-processed foods
- Be cautious with certain food types
- Understand safe levels
- Consider your total exposure
By reading labels carefully, limiting ultra-processed foods, and being aware of familiar sources, you can take steps to avoid excess propylene glycol in your diet. However, small amounts are unlikely to pose significant health risks for most people.