Q: All my adult life, I had problems with foul-smelling gas. This was embarrassing. I also hated that it bothered my wife.

Then, I was diagnosed with celiac disease and had to change my diet. Completely eliminating gluten has also gotten rid of the smells. Others may want to consider this possibility if they have troublesome flatulence.

A: Celiac disease is a condition in which gluten triggers the immune system to attack the lining of the digestive tract. The consequence is poor absorption of nutrients from your diet, and the only effective treatment is to follow a gluten-free diet. That means avoiding any foods made of wheat, barley or rye, because all of them contain gluten.

Symptoms of celiac disease include digestive problems such as diarrhea, cramps, gas or floating feces. Other problems common with celiac disease are anemia, fatigue, osteoporosis, joint pain, headaches and nerve pain.

Blood tests can screen for celiac disease, so others with symptoms like yours should see their doctors.

Q: What’s your assessment of the value of lithium to prevent dementia?

A: There have long been hints that lithium might be valuable to reduce the risk for dementia (Progress in Neuro-Psychopharmacology & Biological Psychiatry, Aug. 30, 2006). However, most research has focused on anti- amyloid drugs such as aducanumab (Aduhelm) or lecanemab (Leqembi). A systematic review turned up a number of animal studies but only a few clinical trials of lithium for preventing dementia (Ageing Research Reviews, March 2024).

Doses studied vary widely. When lithium is prescribed for bipolar disorder, doses range from 600 to 1,800 milligrams daily. Adverse effects may include diarrhea, muscle weakness, drowsiness, changes in thyroid function and kidney damage.

Much lower doses (10 to 20 milligrams of lithium orotate or citrate) have been used experimentally against depression and dementia. The risks may be reduced at such doses. More research is needed on this possible treatment.

Q: My 90-year-old mother lost her marbles quite rapidly. Thank goodness a neurologist tested her vitamin B12 level. He said her level was “within normal range,” but that some older people need more B12 than “normal.”

On hearing that, I gave her over-the-counter sublingual vitamin B12 pills every morning before breakfast. Nearly a week later, she said, ‘I was really crazy, wasn’t I?’

She went on to enjoy the remaining months of her life and died peacefully from unrelated causes. Vitamin B12 made the difference between a dignified end-of-life and pure hell for everyone.

This is a pet cause of mine. I used to work in a nursing home, and I wonder how many people end up in such a place due to a simple undiagnosed vitamin deficiency. Especially if a person seems to go senile very quickly, check their vitamin B12!

A: Older people are vulnerable to vitamin B12 deficiency. That’s because their stomachs may not make enough acid, or they may be taking powerful acid-suppressing drugs (proton pump inhibitors). The body needs acid to absorb vitamin B12.

Symptoms of this B- vitamin deficiency may include difficulties with balance, numbness and tingling of the feet or hands, loss of appetite, memory problems, burning tongue, weakness, constipation or confusion. Restoring vitamin B12 with oral supplements, a transdermal patch or injections usually corrects the problem.

In their column, Joe and Teresa Graedon answer letters from readers. Send questions to them via www.peoplespharmacy.com.