What is lactose?
Lactose is a sugar that occurs only in milk. Digestion requires lactase, an enzyme normally produced by the body. Reduced lactase production can affect lactose digestion.
What causes lactose intolerance?
Lactase production generally decreases with age, but to varying degrees, so only some adults experience difficulty digesting lactose. Genetic variation, certain diseases, and some medications can also reduce or eliminate lactase production.
Prevalence of lactose intolerance
Prevalence of lactose intolerance varies across regions. Countries with a tradition of milk consumption generally show lower rates.
Whey protein use with lactose intolerance
Most people tolerate up to 5 g of lactose per single dose[1], which makes whey protein products suitable for most. Tolerance differs between individuals, however, and a healthcare professional can determine an individual threshold where uncertainty exists.
The content of lactose in whey protein compared to other products
Easing lactose digestion
Pairing lactose-containing dairy with foods from other groups may ease digestion. A lactase supplement is another option for individuals with low endogenous lactase production.
[1] Shaukat A., Lewitt M.D., Taylor B.C., MacDonald R., Shamliyan T.A., Kane R.L., Wilt T.J. Systematic review: Effective management strategies for lactose intolerance. Ann. Intern. Med. 2010;152:797-803. doi: 10.7326/0003-4819-12-201006150-00241.