Endurance sports nutrition advice for those who can’t deal with dairy

If you’re lactose intolerant, you probably know it. The most common symptoms are gas, bloating, and stomach pains following the consumption of milk or dairy foods. Some lactose intolerant individuals are able to consume particular dairy foods (i.e. yogurt) without consequences, others are able to consume small amounts of milk and diary foods with minimal discomfort, while still others must completely avoid all dairy products.

What’s the problem?
Lactose intolerance is caused by the body’s inability to produce an enzyme called lactase that is responsible for digesting the natural lactose sugar in milk. When undigested lactose enters the large intestine, it produces the symptoms that every lactose-intolerant individual knows all too well.

Who’s at risk?
With very rare exceptions, nobody is born lactose intolerant. After all, mother’s milk contains lactose, and infants must produce large quantities of lactase to digest it. Lactase production, however, normally drops significantly after the age of weaning. But the amount of that decrease varies significantly between individuals, depending largely on ethnicity. Persons with northern European ancestry tend to continue producing enough lactase to drink milk throughout life, whereas persons of African, Asian, and Native American ancestries typically become lactose intolerant. There are plenty of exceptions, though, and even many who can consume diary foods as young adults develop problems later in life due to a continuing decline in lactase production.

How do you treat it?
Dealing with lactose intolerance is a fairly straightforward matter. Just avoid consuming the dairy foods that give you problems, or limit your consumption of such foods to amounts that do not produce symptoms. It may take a little trial and error to figure out exactly what you can and cannot get away with.

Why should endurance athletes be careful when ditching dairy?
Excluding diary foods from your diet means missing out on the unique combination of nutrients they provide—particularly protein and calcium, which are very important to those in marathon training, triathlon training, or any other endurance sport training. Fortunately, many other foods are rich in protein, such as meat, eggs, fish, and nuts. But when it comes to calcium, dairy foods contain much greater amounts of the mineral than almost any other foods. The average American already gets significantly less than the recommended amount of calcium per day (1,000 mg for men and 1,300 mg for women), and if you do not consume any dairy foods due to lactose intolerance, it is even more likely that your calcium intake will fall short—unless you make a consistent effort to get calcium from other sources.

Which calcium sources are best for lactose intolerant individuals?
The top non-dairy natural sources of calcium are sardines (324 mg per serving), tofu (138 mg per serving), and dark green leafy vegetables such as spinach (120 mg per serving). You can get additional calcium from fortified foods and beverages, including many breads and breakfast cereals and some juices. Read labels to find out whether specific products are calcium fortified. Finally, for insurance, you can take a daily calcium supplement or multivitamin-multimineral with calcium.