The design of the human body shows remarkable adaptation to our immediate environment. Whenever a foreign element is detected, the autoimmune system is there for our defense. Whatever the problem, the white cells rally round and fight the invasion. Because our body learns about new strains of bacteria and viruses all the time, it’s constantly modifying the way the autoimmune system works to give us the best possible protection. If it cannot beat the invader, the body tries to adjust its chemistry to reduce the adverse effect. Overall, we do well in our increasingly complicated environment.

To the body, the chemicals we take as medication are also invaders in the bloodstream. Sadly, we can’t send a message to the white cells telling them these chemicals are new friends. Everything is an enemy to be destroyed. This is really bad news. When the drugs first arrive in our bloodstream, the effect is exactly as predicted by the research team that designed the drug. An unprepared body always reacts with the most beneficial results in the first few hours. But as time passes, the autoimmune system gets to work and it adapts the body to reduce the effect of the chemicals. Doctors call the result tolerance. Our body grows used to have the drug in the bloodstream and the beneficial effect slowly disappears. The only ways of dealing with this are either to increase the dose or to switch to a new drug. Unfortunately, all this does is buy time. Sooner or later, tolerance builds up again and we are back to the same decision.

The proton pump inhibitors are not addictive in the same sense as, say, the opiate painkillers, but they are subject to the same problem of tolerance. If you take any of these drugs over time, you will slowly have to increase the dose to get the same effect. Until recently, this was not thought a problem but recent studies now suggest a problem for menopausal women. Any woman over the age of 50 who begins to go through the menopause will lose calcium. Osteoporosis is a well-recognized problem and doctors usually advise women to take calcium supplements to retain bone density. It’s now clear the use of drugs like Nexium may be accelerating the calcium loss. When the proton pump is slowed and the amount of acid is reduced, the body also reacts by changing the volume and type of enzymes produced. This is intended to improve the digestion system but it can also affect the way in which the dissolved food is processed. The recent studies suggest the increase in some enzymes slows the rate at which calcium is absorbed. Even if you are taking a calcium supplement, you may be losing bone density.

The moral of this most recent study could not be more clear. Men do not seem to be at risk in the same way but, for women, the best possible chance of retaining bone density seems to be stopping the use of Nexium as you go through the menopause. To avoid the return of heartburn, this will involve changing your diet to reduce the amount of high-fat. But, if you retain strength and lose weight, you get a double benefit.