They are a ghastly orange color when they tumble out of their crinkly package with its flamelike logo, and salt mines and chemical plants may come to mind when you eat the first one, but, man, those tortilla chips are tasty. Or maybe it’s just that you can actually taste them. Because sorry, Charlie: as we get older, there may come a time when we find ourselves drawn not to food with good taste or food that tastes good but simply to food that has any flavor at all.

Blame your aging taste buds, if you want. You’ll probably be wrong, but there are a lot more of them (about 9,000) to point the finger at than the likely real culprit, your nose. “When people talk about their taste, they’re really talking about the smell rather than the taste,” said Dr. Scott P. Stringer, chairman of the otolaryngology department at the University of Mississippi Medical Center.

As it happens, taste buds do diminish as people get older, usually starting at 40 to 50 in women and 50 to 60 in men (why later for them is unknown). And those that remain do not, so to speak, step up to the plate to make up for their departed colleagues. No, they begin to atrophy, and sometime around age 60, people may notice that they have lost some taste sensation, usually beginning with salty and sweet tastes and then bitter and sour ones.

But it is the changes in the nose that really matter. Among them, said Dr. Stringer, a member of the American Academy of Otolaryngology – Head and Neck Surgery, are a decrease in the number of sensor cells that detect aromas. These cells routinely die out and are replaced, but in older people the replacement process does not work as well.

There are also declines in the nerves that carry the signals to the brain, and in the olfactory bulb, which processes them. Beyond that, the sense of smell may also be diminished by a reduction in the amount of mucous that is produced, a thinning of the nose lining and hormonal changes. (Some diseases, injuries to the head and some medicines may also affect smell.)

The decrease in the sense of smell and taste occurs gradually, and many people do not realize what is happening. Some never realize any change at all, researchers have found after studying subjects who said their sense of smell was fine but were unable to detect some aromas.

In some cases, if the loss of smell is severe enough, it can pose serious risks. A study published in 2006 in Science of Aging Knowledge Environment found that 45 percent of the elderly subjects tested could not detect the warning odor in natural gas. Food may also become less appealing, leading to nutrition problems among older people who stop eating as much as they should.

Then there are those who, in a quest for flavor, may seek out foods higher in salt and sugar. This can make other health conditions worse. To say nothing about those orange fingertips.