Optimal hydration: The Osmolality Lab unlocks effective functional beverages

30 Jul 2024 --- As climate researchers predict another summer with record-high temperatures, the Osmolality Lab highlights the importance of measuring beverages’ osmolality range to create drinks with optimal hydration. This is a research, testing and certification company for hydration beverage products. 

Nutrition Insight meets with Dr. Nick Gillitt, the company’s CEO, to discuss beverages’ optimal osmolality range and formulation challenges.

“Scientifically speaking, osmolality is a physical attribute of a liquid,” says Gillitt. “Osmolality levels are determined by the amount of dissolved solids in that liquid and expressed in units called milliosmoles per kilogram (mOsm/kg).” 

“Notably, it confers something called osmotic pressure on a liquid, which affects the movement of water to and from the liquid in the environment in which it is placed. This is important in the body as you want the water you put in it, by drinking a beverage, to be absorbed.” 

He explains that the ideal biological situation occurs when the beverage’s osmolality and the surrounding tissues are similar, allowing efficient absorption. “Issues arise when they are markedly different.” 

Optimal hydration 
Gillitt highlights that there are substantial opportunities to create hydrating beverages. 

“It’s a big market, and the world is only getting hotter. Hydration is very important for normal biological function, as we need to be hydrated to allow our metabolism to do its job (to cool down by sweating, for example).” 

Drinks with optimal hydration conserve as much of the water contained in them as possible, he explains. “The WHO and UNICEF looked at many studies and determined the optimal osmolality to be within a range of 210–268 mOSm/kg and The Osmolality Lab measures and certifies leading and innovative hydration and rehydration brands within this range.”

“Research shows that when a beverage has an osmolality in this range, you will retain a significant portion of the liquid (i.e., you become hydrated) rather than expelling it eventually as urine. The more liquid you keep in your body, the more hydrated you become.” 

“If you are dehydrated due to exercise, time spent in hot environments or other factors, getting hydrated quickly can be paramount. The best way to do this quickly, short of an IV, is to drink a beverage with the appropriate osmolality.” 

For efficient absorption, a beverage’s osmolality (determined by dissolved solids in a liquid) and surrounding tissues are similar.Osmolality balance 
Although water has an osmolality of zero, this doesn’t mean it doesn’t hydrate. Gillitt notes that drinking water is an excellent strategy for maintaining a hydrated state. 

“However, an osmolality that is too high can initially have a dehydrating effect, as the surrounding cells will release water to lower the osmolality of the local environment. So, there is a balance needed for efficient hydration. Beverages with the right osmolality are the most effective, especially if you have become dehydrated and time is of the essence.” 

“Osmolality requires dissolved solids,” he continues. “When considering what to put into a beverage to increase its osmolality, companies will typically use carbohydrates and electrolytes. The key is understanding and determining the right amount to add to achieve the required osmolality range.”

Everything dissolved in a beverage formulation, including flavor systems, contributes to its osmolality. “As we continue to learn more about nutrition and nutrients, new ingredients will come into the picture.” 

Formulation challenge 
Gillitt underscores that if people are dehydrated, they need the best products available for rehydration. 

“The challenge lies in the formulation: beverages need the right osmolality to be hydrating, but they also have to taste good, look appealing and not contribute to certain unhealthy behaviors, such as too much added sugars or sodium. Overall, these challenges are surmountable with good formulations. There’s no reason a hydration drink can’t be the best at hydrating while being nutritious and refreshing.”

Consumers cannot determine a beverage’s osmolality from the nutrition label alone, cautions Gillitt. 

“Although it will show you how many carbs (usually sugars) and electrolytes (sodium, potassium, magnesium and calcium) are present, while these are all dissolved solids and contribute to osmolality, generally, you can’t determine the osmolality value itself.” 

Gillitt advises manufacturers to start measuring the osmolality of their products to see where these fall in established recommendations.The Osmolality Lab supports manufacturers by providing an indicator of “best-in-class” hydration. 

“While many companies claim hydration in their products, they do not fall within the optimal osmolality range. Even if a company’s existing product is slightly too high or too low, it’s easy to adjust formulations or serving instructions to correct this.” 

Beverages market 
According to Gillitt, the hydration market is “very crowded.” He observes that hundreds of brands with high-profile spokespeople make hydration claims. 

“In such a crowded marketplace, a science-based differentiator like The Osmolality Lab’s certification program can help consumers make more informed choices and buy products that actually work. It can also encourage manufacturers to adopt osmolality testing during the product development phase so that better products enter the marketplace.” 

He advises manufacturers to start measuring the osmolality of their products to see where these fall in the WHO/UNICEF recommendations. “This measure should be used as a product development tool, especially if they claim or intend to claim optimum hydration.” 

The Osmolality Lab measures osmolality in consumer products. It certifies beverages that fall within this range to indicate to consumers that a product is “osmolality appropriate for its hydration or rehydration claims.” 

By Jolanda van Hal