Dear Dr. Roach: I love salt, although I know it is dangerous to eat a lot of it. To compensate, I visit the steam room for a half-hour every day and sweat, which also causes me to drink plenty of water. Is this sufficient to nullify the negative effects of eating salt?
C.J.
Salt increases blood pressure a little bit in most people and a whole lot in a few people, so the first question to answer is whether your blood pressure is high. If it is, then you certainly should be consuming less salt.
There also is some evidence that even in people without high blood pressure, salt can increase risk for other problems. One study showed an increase in stroke risk from excess salt intake, even in people with normal blood pressure. Kidney stone risk is higher with high salt consumption.
As far as sweating goes, even though sweat tastes salty, it鈥檚 not an effective way to get rid of salt, for most people. Athletes competing in the heat can lose up to
350 mg of salt in a half-hour. People who are in the top 25 per cent of North Americans for salt consumption get 5,000-10,000 mg of salt in a day. By contrast, the recommended amount of sodium intake in a day is 2,300 mg. Endurance athletes and workers doing physically demanding work in a hot environment for eight to 12 hours per day might need to consume additional salt; however, they are the exceptions.
Drinking plenty of water helps the kidneys get rid of sodium, but I think that cutting down on salt is more likely to reduce your risk of serious diseases.
There are cooking techniques to help make food more flavourful without using lots of salt. A registered nutritionist or dietitian can be of benefit in this.
Dear Dr. Roach: My child might have common variable immunodeficiency. He doesn鈥檛 seem to be responding to vaccines, as measured by blood titers. Is CVID one of the things that are a contraindication of vaccines?
C.B.
Common variable immunodeficiency is a primary immune system disease: People are born with it, and because it is variable, it can be diagnosed early in childhood or not until adulthood (if ever). People with CVID have difficulty making antibodies, and their antibody levels are low; sometimes specific antibodies to vaccine-preventable diseases are insufficient. People who do not produce antibodies despite vaccines are generally treated with immune globulin (IgG). This provides some protection against common infections. Because this disease is variable, exact recommendations should be made by your child鈥檚 doctor, preferably a specialist in primary immunodeficiencies.
Two live vaccines, yellow fever and oral polio, should not be given to most people with CVID. These are not part of the standard vaccinations for children. Killed vaccines, such as what is used for the flu shot and pneumonia shot, generally are recommended, although they might not work well, especially if a person is treated with IgG. Most other vaccines are given per the usual schedule. The MMR vaccine needs individual consideration.
Lots more information is available from the Immune Deficiency Foundation (primaryimmune.org) and the Jeffrey Modell Foundation (info4pi.org).
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].
