Health A-Z

Lactose intolerance: 'Is sourdough bread the cause of my lactose

Lactose is a natural sugar that is broken down in the small intestine into two other sugars – glucose and galactose – which are absorbed into cells. If you are lacking in lactase, the enzyme that breaks down lactose, then the lactose will remain in the intestine. When it reaches the large intestine it begins to ferment, leading to the production of gases that cause wind, cramps and other symptoms. Sourdough bread does not contain lactose, so your symptoms must have another cause.

Hip replacement: The risks

"I had a total hip replacement, and now that leg is two inches longer than the other. The surgeon is mystified. Was the prosthesis the wrong size?"

Smell: 'I've lost my sense of smell. Is it age-related?

Vision and hearing tend to deteriorate with age, but smell usually holds up well. Losing it can be the first sign of something serious. Alzheimer's and Parkinson's can start with the loss of sense of smell. It can also be caused by a head or nose injury that damages the olfactory nerves. Slow-growing brain tumours can press on the olfactory nerves, preventing them working. But a far more common cause is allergy, leading to the lining of your nose becoming swollen and inflamed. There are treatments for allergic nasal problems that can restore your smell to normal. First, get a proper diagnosis, via referral to an ENT or allergy specialist. Allergies to simple things, like dust, feathers and household pets, can cause this kind of problem.

Stomach gas: What's wrong and how can it be cured?

You could be lactose intolerant. Lactose is the natural sugar that is present in milk products. People who are lactose intolerant cannot digest it because they are lacking an enzyme called lactase, which breaks lactose down into glucose and galactose. Undigested lactose ferments in the stomach, causing a build-up of gas. Even if you were not lactose intolerant when you were younger, you may develop it, as it becomes more common with age. If you don't want to take a test to see if you are lactose intolerant, you could try to reduce or eliminate lactose from your diet and see if you are any better.

Memory loss: Will sage oil help?

In 2003, scientists at Newcastle University found that sage had a beneficial effect on memory. They used capsules that contained 50 microlitres of sage extract in sunflower oil. Have a look at the label on your capsules to get a dose similar to this. A few patients may develop raised blood pressure when taking sage, so if you have high blood pressure, avoid sage.

Simvastatin and grapefruit: Are they compatible?

To answer this question properly, I bought a medium-sized (300g) grapefruit. I squeezed all the juice out of half of it, producing 70ml of juice. The original research into grapefruit juice and simvastatin looked at the effect of 200ml of grapefruit juice. The juice from half a grapefruit is about one-third of this amount. Even this amount will cause some people problems. The effect of each dose of grapefruit juice lasts for several days, so if you have half a grapefruit every morning the effect accumulates. My advice is to stick to oranges and orange juice if you are taking statins.