DEAR DR. DONOHUE: No matter what I do, no matter what I eat, no matter how many times a day I brush my teeth, I can’t get rid of my bad breath. This is taking a toll on my social life. I have become very self-conscious. Do you have any suggestions? – J.A.

ANSWER: Have your breath judged by a third party, one you know will give you an honest appraisal. Your subjective evaluation of your own breath might not be accurate.

Close to 90 percent of bad breath originates in the mouth, and close to 90 percent of it is due to bacteria in the mouth. The other 10 percent of bad breath comes from locations in the lung, the sinuses, the nose, the digestive tract, the liver or the kidney.

Mouth bacteria produce sulfur byproducts that are gaseous and are breathed out as most unpleasant odors. Those bacteria reside between the teeth and on the backmost part of the tongue. Flossing teeth and brushing the farthermost reaches of the tongue can get rid of those bacteria. A dry mouth is another source of bad breath. Chewing sugarless gum can keep saliva flowing and the mouth fresh.

A low-fat, almost vegetarian diet is less likely to generate unpleasant mouth odors than is a high-in-meat diet. Some doctors feel H. pylori, a bacterial resident of the stomach, is responsible for bad breath, but there is no consensus on this.

I have heard testimonials that say six weeks of eating sugar-free yogurt freshens the breath. I can’t guarantee the effectiveness of this. If none of the above frees you from halitosis, then it’s time to look for those things that cause the 10 percent of bad-breath cases – lung infections, sinusitis, postnasal drip, acid reflux and the rest.

DEAR DR. DONOHUE: This is day 22 of my no eat/no drink diet. I haven’t had anything to eat or drink for that long.

Will this diet rid my body of sugar, salt, fat, cholesterol and plaque? How long should I continue? – R.T.

ANSWER: This diet will rid you of life. You have to be putting me on. You couldn’t have the energy to write a letter, put a stamp on the envelope and take it to the post office if you haven’t eaten or drunk in more than three weeks. People usually die within about two weeks of not eating or drinking.

Write back and tell me this was a joke. Why would you want to rid your body of all sugar, salt, fat and cholesterol? They’re all needed for health.

DEAR DR. DONOHUE: I saw my doctor for chest pain. He sent me to the hospital for heart tests. The tests showed that I had an enlarged aorta. The doctor didn’t seem concerned, so I didn’t press for answers. I did ask him if there was something I should do, and he said no but that he would check it again. That was more than a year ago.

I just turned 79 and, for the most part, feel pretty healthy. I drive my own car and pick up friends when we go out. I would like your opinion about my aorta.

ANSWER: Your doctor wouldn’t let a dangerous aortic condition go untreated. The aorta is the large artery that springs from the heart and travels all the way to the bottom of the abdomen, where it divides into two arteries for the legs.

Prominent aortas (enlarged) are common. If they don’t exceed a certain size, nothing need be done. I have to believe yours is big but not so big that it’s a threat to your health. You don’t need to do anything other than what any other 79-year-old would need to do – keep your weight down, exercise daily, watch your cholesterol and blood pressure, and stay as active as you can.

An enlarged aorta makes one think of an aneurysm – a bulge that represents a weak spot. Your doctor would have told you that you had an aneurysm if you really had one. I hesitate to mention this because it might make you worry. That’s the last thing you need to do. You should remind your doctor of his promise to check the aorta again.

DEAR DR. DONOHUE: Two close friends recently died from ARDS. Although we know nothing about it, we figure it must be common, or it wouldn’t have struck these people within a week of each other. Is this the same lung problem that spread from China a few years ago? Is it contagious? – R.S.

ANSWER: ARDS, acute respiratory distress syndrome, is neither common nor rare. An injury to the lungs causes lung air sacs (alveoli) to fill with fluid. The result is severe shortness of breath and a greatly reduced amount of oxygen in the blood. The person pants rapidly in order to trap all the air possible.

The triggering injury can be a critical infection like sepsis (blood infection), pneumonia, chest trauma, smoke inhalation, sickle cell anemia or a reaction to medicines.

The first phase of the illness consists of fluid filling the air sacs, and this phase lasts about a week. Then the second phase sets in, during which the body tries to clean up the liquid mess in the lungs. Some are unable to meet the challenge and succumb. Others get rid of the fluid but enter a third phase where there is deposition of scar tissue in the lungs. This leaves them with permanent lung disability. Age plays a great role in the outcome. People over 75 have a 60 percent mortality rate from ARDS, and those younger than 45, a 20 percent mortality rate.

For those between the ages of 45 and 75, the mortality rate is between 20 percent and 60 percent. Some recover completely.

Although many medicines have been used to stem the onslaught of ARDS, there is no one medicine that has won universal approval. Mechanical ventilation is the accepted treatment.

This is not a contagious illness, and not the one that spread from China in 2003. That illness is SARS, severe acute respiratory syndrome. Whoever made up these names – ARDS and SARS – should be put on trial for confusing everyone. SARS is an infectious disease. A virus called coronavirus causes it. It has a mortality rate of 11 percent, regardless of age. In 2003, SARS caused 251 deaths in Canada and 29 in the United States. It also caused a worldwide panic.

Dr. Donohue regrets that he is unable to answer individual letters, but he will incorporate them in his column whenever possible. Readers may write him or request an order form of available health newsletters at P.O. Box 536475, Orlando, FL 32853-6475. Readers may also order health newsletters from www.rbmamall.com