DEAR DR. ROACH: I take Centrum Silver supplements and noticed that my blood pressure went up. I noticed that, as with other supplements, it contains sodium, such as sodium ascorbate and sodium selenite. How can all this sodium be good for you? — O.R.

ANSWER: Centrum, like many other products, contains a wide range of vitamins and minerals. The minerals in particular have to be in a chemical form that the body can absorb, and that means as a salt with another mineral. Sodium selenite, for example, is an easily absorbable form of selenium. Copper can’t be absorbed as a metal, but as a salt with sulfate, it can be. However, the amount of minerals in the supplement is very small.

I contacted the manufacturer, and the total sodium content of a Centrum Silver adult tablet is 0.59 mg. Compare that with about 10 mg of sodium on a single potato chip, and you will see that it’s a very small amount of sodium, not enough to cause your blood pressure to increase. It’s very likely that there is another cause that made your blood pressure go up, perhaps something you started at about the same time as the supplement. It’s also possible that just being worried about the sodium is making you nervous when your blood pressure is checked, artificially raising the reading.

Many people take regular supplements for a variety of reasons; however, most people with a diverse, healthy diet with plenty of different vegetables and fruits do not need, and probably don’t benefit from, a daily supplement.

DEAR DR. ROACH: Recently, you wrote that there is no way to lose weight in a specific place, but I have read about laser devices that literally melt the fat away. Is this true, or is it 21st-century snake oil? — J.J.

ANSWER: I should have said that there isn’t a way through diet and exercise to preferentially lose fat from one area of the body, but a surgeon certainly is able to remove cosmetically important amounts of fat from specific areas. Liposuction has been an effective way of doing so for years, but there are new, less-invasive methods, such as cooling and laser devices. These cause damage to the fat cells, which die, and I have seen photographs that show improved appearance to abdominal fat after treatment. However, the fat doesn’t leave the body: It is reabsorbed and put somewhere else, unless the person is on a (successful) diet and exercise plan. The goal of laser and cooling devices is improved looks, which is important, but if the goal is improved health, you still need to adopt a healthier lifestyle.

Finally, the “belly fat” referred to is fat inside the peritoneal cavity. That is the fat that is metabolically active and increases risk of heart disease. It is not affected by liposuction, nor by these newer, less-invasive techniques.

DEAR DR. ROACH: I read that more people younger than 50 are being diagnosed with colon cancer. Do you think people under 50 of average risk should ask for colorectal cancer screening? — P.S.

ANSWER: At my institution as well, we certainly are seeing younger patients more frequently. Until the guidelines get revised, if they do, I think everybody should be knowledgeable about their family history. There remains some stigma about colon cancer, and a positive family history, certainly of colon but also of unknown or “stomach” cancer, should prompt a discussion about screening.

Finally, anyone diagnosed with colon cancer should speak with his or her family about it, and also ensure that the cancer is tested for familial cancer syndromes, such as Lynch syndrome.

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Dr. Roach regrets that he is unable to answer individual letters, but will incorporate them in the column whenever possible. Readers may email questions to [email protected] or request an order form of available health newsletters at 628 Virginia Dr., Orlando, FL 32803. Health newsletters may be ordered from

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