After 40, our bodies naturally start losing muscle and strength: a process known as sarcopenia. It’s part of aging, but the pace of this decline depends strongly on how we conduct and nourish ourselves. To slow it down and stay strong, we actually need more high-quality protein than we did in our 20s or 30s.
Over time, muscles become less responsive to amino acids, meaning that older adults need a higher protein intake to achieve the same benefits as in their younger years. This phenomenon is known as anabolic resistance. (1)
Unfortunately, most adults eat less protein as they age, even though their bodies need more to maintain muscle, bone health, and metabolism.
Proteins are essential nutritional building blocks. But not all proteins are created equal. Their structure, digestibility and amino acid composition determine how effectively the body can use them.
Among milk proteins, beta-lactoglobulin (BLG) stands out for its exceptional amino acid profile, high bioavailability and particularly high leucine content, which supports muscle and metabolic health. (2)
Until now, BLG has been available only in limited quantities, due to the complexity and cost of extracting it from milk.
At 21st.BIO, we’ve developed precision fermentation technology that can produce BLG cost-effectively and with consistent high quality and purity. It uses far fewer resources than traditional dairy. It is 10 times more efficient than the cow in converting feedstock to high quality protein. And then it contains no fat or lactose.
Our BLG is already approved for sale in the U.S.
Of course, nutrition is about more than protein alone. But access to high-quality protein is emerging as one of the defining challenges of the next decade. Global demand for milk protein is expected to outpace supply, and many industry insiders predict a real “protein gap” by 2030 – one that could limit access to essential nutrition, particularly for vulnerable populations.
Precision fermentation can help close this gap: offering a sustainable, locally produced source of high-quality proteins at price parity.
That’s one of the most exciting promises of biotechnology: enabling better nutrition for a growing world, without exhausting the planet’s resources.
(1) Robert W. Morton et al., “Defining anabolic resistance: implications for delivery of clinical care nutrition” (2018)
(2) Morten Hostrup et al., “β-Lactoglobulin: A novel bioactive whey protein with incretin-modulating and muscle anabolic properties” (2025)
