DEAR DR. BLONZ: I am lactose-intolerant, so I have become a careful label-reader. I remain curious and cautious about some ingredients in bread and lunchmeat products that sound as if they might contain lactose. Two that I often see are “potassium lactate” and “sodium lactate.” Are these sources of lactose, and if so, how much (in relation to milk)? Also, seeing as it is a dairy product, is there lactose in butter? -- K.D.B., via email
DEAR K.D.B.: Lactose is the main carbohydrate (sugar) in milk and milk products; it is a double sugar made up of glucose attached to galactose.
Lactose intolerance reflects an inability to effectively separate the lactose into its constituent parts, which prevents it from being absorbed. The undigested lactose travels the length of the digestive tract, enters the large intestine and, depending on how much arrives, can cause various degrees of bloating, gas, diarrhea and nausea.
An 8-ounce glass of milk contains about 12 grams of lactose. As you have observed, there are food additives where lactose is a part of a compound. Potassium lactate and sodium lactate are just such substances; another is calcium lactate. These compounds can act as a buffer and help protect against product breakdown. Such “lactate” compounds tend to be used at milligram levels, so they should not represent a concern for any typical lactose-intolerant individual. The same can be said for butter, which is very low in lactose, containing about half a gram per serving.
If you are extremely sensitive to lactose, you will have to experiment to see how your body reacts. The University of Virginia sheet on the lactose content of various dairy foods can be found at tinyurl.com/yc7a2ywn.
DEAR DR. BLONZ: My grandson is now into bodybuilding. His high school trainer says he needs 200 grams a day of quality protein, plus a gallon of water. This seems excessive and I don’t want him to damage his kidneys. What are your thoughts? -- I.K., San Jose, California
DEAR I.K.: You did not indicate what your grandson weighs, and protein intake in athletes tends to correlate with their body weight. An average individual needs about 0.8 grams of protein per kilogram of body weight. For a 176-pound (80 kg) individual, this equates to 64 grams of protein a day. A generous intake for a strength-training athlete is between 1.2 grams and 2 grams per kilogram,
which translates to 96 to 160 grams of protein per day.
There is little evidence that higher protein intakes provide any additional benefit. The flip side is whether having excess protein might cause problems. As with any caloric food, excess protein gets disassembled, the kidneys having the task of removing the amino-group nitrogen from the body. Some of protein’s amino acids can be turned into glucose if that is needed at the moment, but most gets turned into fat and packaged for storage. We know what that means.
Assuming your grandson remains well-hydrated (the gallon a day speaks well to this aspect), and the rest of his diet contains greens, grains, fruits and vegetables, there are only minimal risks from this level of protein. There is a good discussion of protein requirements for athletes at tinyurl.com/zoq668l.
Send questions to: “On Nutrition,” Ed Blonz, c/o Andrews McMeel Syndication, 1130 Walnut St., Kansas City, MO, 64106. Send email inquiries to firstname.lastname@example.org. Due to the volume of mail, personal replies cannot be provided.