On Nutrition by Ed Blonz

White and Dark Meat, Crab Tiredness

DEAR DR. BLONZ: My question is about chicken meat and fat and the differences between the white and dark meats. I eat a healthy diet but must confess a slight bit of guilt in that when eating chicken, I prefer the taste of dark meat to white meat. I discard the skin and visible fat when cooking chicken thighs and breast pieces, but does dark meat still contain more fat than white? -- B.C., Concord, California

DEAR B.C.: Stored calories in chicken, otherwise known as chicken fat, are under the skin, but some is also deposited around the individual muscle groups. The larger breast muscle doesn’t do much work because chickens are flightless birds. Not so for those leg muscles. There are many different bundles of muscles, each requiring an efficient blood supply and available energy. As domestic chickens tend to hang around and eat all day, they tend to always be in a positive caloric balance. This favors the laying down of body fat, some of which gets stashed in and around the muscles. (The same thing happens to us!) With the working muscles of the legs, there are more opportunities for fat to hide, which explains why dark meat tends to have more fat than white meat.

The “dark” of dark meat doesn’t come from fat; it comes from myoglobin, an oxygen-carrying pigment that is present to a greater degree in working muscles. Breast meat is lighter because it contains lesser amounts of myoglobin. Consistent with this theme, the breast meat of birds that fly, such as duck or goose, is not considered “white meat.”

Go ahead and remove the visible fat as best you can, but even then, there will still be a bit more fat in the dark meat. But you mention that you eat a healthful diet; so why not consider discarding that guilt and simply sticking with the type of meat you enjoy?

DEAR DR. BLONZ: My wife and I love crab. When it is in season, we tend to have a family feast, but afterward, we tend to experience tiredness even into the next day. Is this some sort of coincidence or is there a chemical reason for this? -- C.D., San Diego, California

DEAR C.D.: It’s not likely the crab, at least not by itself. If, however, you tend to have a full plate, and you couple the crab with a high-carbohydrate side dish or a sweet dessert, the combination may be causing a seafood version of the protein-carbohydrate tiredness typically associated with a Thanksgiving feast. The relative amount of the amino acid tryptophan tends to be higher in crab than in other types of protein. When consumed as a part of a big meal that contains carbohydrates, this can give rise to increased production of serotonin in the brain that can contribute to relaxation. It is unclear how this would overflow to the next day unless a leftovers feast continued on the following day, or if the associated toils of the family event had interrupted your normal sleep pattern.

Send questions to: “On Nutrition,” Ed Blonz, c/o Andrews McMeel Syndication, 1130 Walnut St., Kansas City, MO, 64106. Send email inquiries to questions@blonz.com. Due to the volume of mail, personal replies cannot be provided.