Sugar beet became a major source of sugar in the 19th century when methods for extracting the sugar became available. Sugar beets are a cultivated variety of Beta vulgaris, a tuberous root containing a high proportion of sucrose.

Sugarcane refers to several species of giant grasses in the genus Saccharum. They have been cultivated in tropical climates in South Asia and Southeast Asia since ancient times. Sugarcane is milled and the juice is extracted with water or by diffusion. The liquid is then clarified, with the resulting fluid concentrated in a series of evaporators. Sugar crystallizes out, is separated from the sugarcane juice and then dried.

Molasses is a byproduct of sugarcane processing. Fiber from sugarcane stems, known as bagasse, is burned to provide energy for the sugar extraction process. The crystals of raw sugar are covered in a sticky brown coating and can be used as is, can be bleached by sulfur dioxide, or can be treated to produce a whiter product like granulated table sugar. Refined sugar comes from raw sugar that has been processed to remove the molasses. Raw sugar is sucrose which has been extracted from sugarcane or sugar beet. Though raw sugar is edible, the refining process removes undesirable flavors and results in refined sugar or white sugar.

Other types of sugar include brown sugar which either contains residual molasses or has the grains deliberately coated with molasses to produce a light or dark colored sugar. Cane juice, which has many regional and commercial names including demerara, muscovado, turbinado sugar, Florida Crystals and Sucanat, are all made from sugarcane. Palm sugar is created by tapping the flowering stalk of various palms to collect the sap (similar to maple syrup production). The most commonly used species for this is the Indian date palm (Phoenix sylvestris), but other species like coconut (Cocos nucifera) palms are also used.

In cosmetic applications, sugar acts as a humectant. Without getting technical, the principal purpose of a humectant is to form hydrogen bonds with molecules of water. Humectants help your skin better retain moisture.

Sugar also contains an alpha hydroxy acid (AHA) commonly referred to as glycolic acid. AHA’s, such as glycolic acid, help remove dead (keratinized) cells in your skin’s outermost layer (called the stratum corneum). The increase in cellular turnover (sloughing) exposes younger cells and a clearer complexion.

The physical properties of sugar, namely its shape as small, rough crystals make it a great exfoliant. However, larger crystals can damage the skin by cutting too deep into the epidermis and causing micro-tears in the living dermis below. For this reason, it is wise to assess the size and shape of the sugar crystals you plan to use and then consider the application of the cosmetic product you are formulating. Small, uniform grains are most effective in products formulated for facial application. More substantial, angular grains are most effective on the thick and rough skin found on feet, knees and elbows.

Notably, there have been numerous studies on the effects of topical sugar and wound care. While most of the studies discuss the use of topical sugar in diabetic ulcers, some also address the use of sugar in the care of burns. Results of one study showed reduced wound edema, the formation of granulation tissue (new vascular tissue on the surface of a wound), lower wound pH, bacterial lysis and inhibited bacterial growth. As cosmetic formulators, we cannot address medical applications of cosmetic ingredients, but the studies also discussed the use of topical sugar by those with diabetes. Specifically that since sucrose is not metabolized outside the intestinal tract; local application of sugar should not be expected to lead to systemic absorption or changes in blood sugar. For the layperson, this means cosmetics like sugar scrub are unlikely to affect our diabetic customers.

Beyond sugar as an ingredient, there exists an entire market of cosmetic ingredients derived from sugar. Common sugar-derived ingredients are lactic acid, squalane and hemisqualane, propanediol, emulsifiers and rheology modifiers (thickeners). You can even find cosmetic-grade sugarcane extract to add moisturizing and skin-conditioning properties to your formulations without using raw sugar.

If you primarily formulate “natural” cosmetics, sugar can be a useful and “consumer-identifiable” option, but there are also caveats to these ingredients. Sugar beets are often genetically modified. For clients demanding non-GMO ingredients this may cause a snag; however, there is no genetically modified sugarcane. Be aware of the source of your sugar. Additionally, refined sugar cane gets filtered through charcoal (often made from animal bones) to remove impurities and odor. If your client base is vegan, this is unacceptable. Sugar from sugar beets is never processed through bone charcoal and Certified Organic sugar does not permit the use of “bone char” as a processing aid, so these sugars are used in vegan cosmetics without issue. And, for those primarily concerned with sustainability, there are four voluntary initiatives to help ensure sustainability of the sugar you use: Organic, Fair-trade, Rainforest Alliance, and Bonsucro.

References:

Biswas A, Bharara M, Hurst C, Gruessner R, Armstrong D, Rilo H. Use of Sugar on the Healing of Diabetic Ulcers: A Review. Journal of Diabetes Science and Technology. 2010;4(5):1139-1145.
State of Sustainability Initiatives: Sugar Market https://www.iisd.org/ssi/sugar-market/
Is Sugar Vegan? PETA: https://www.peta.org/living/food/is-sugar-vegan/