Consuming 64 ounces water daily could be ‘unscientific’

Q: We have heard for years that we are supposed to drink eight 8-ounce glasses of water every day. Yet, no one has ever bothered to tackle the other side of that equation. That is 64 ounces of liquid with perhaps many more from other sources throughout the day.

How many times am I going to go to the bathroom during the day and night? I don’t think that all this liquid can be eliminated before bedtime. Some inevitably filters through and causes nighttime bathroom jaunts.

A: There has been a great deal of confusion about the “8 x 8” (8 ounces of water, eight times a day). Some researchers call this recommendation unscientific. Others point out that you get liquid from other sources besides drinking plain water (Nutrients, Oct. 31, 2020).

Older people may be vulnerable to dehydration if they don’t drink enough fluid, especially during hot weather. On the other hand, your point is pertinent that drinking a lot of water will result in a lot of nighttime trips to the bathroom.

Q: Many years ago, I complained to my doctor about restless legs. She prescribed folic acid (1 milligram daily). It has to be prescription, not over the counter. It works! A:

Folic acid is a B vitamin. The 1 milligram dose is available both by prescription as well as over the counter. The recommended daily allowance is 400 micrograms, less than half the amount you are taking.

We searched high and low and could find no good evidence to support the use of folic acid supplements to treat restless leg syndrome. Many doctors consider this supplement innocuous, since B vitamins are water soluble.

There is one caution, however. A recent study based on data from the U.K. Biobank found an unexpected link between prescribed folic acid supplements and susceptibility to COVID-19 (BMJ Open, Aug. 24, 2022). Even worse, people who caught COVID-19 while taking high-dose folic acid were more than twice as likely to die of the infection. The authors suggest that this B vitamin may make it easier for the virus to multiply.

Q: You’ve written about the possible benefits of vitamin D to boost immunity and protect people from infection. So perhaps you won’t like this at all. There are studies showing that vitamin D does not help prevent COVID-19! What do you think? A:

Thank you for bringing this research to our attention. Both studies were recently published

in the BMJ. One of the studies included 6,200 British adults who had not been taking vitamin D (BMJ, Sep. 7, 2022). The researchers tested blood levels of the study volunteers and assigned them on a random basis to get vitamin D supplements or not. During the six-month follow-up period, people taking vitamin D were no less likely to come down with a respiratory tract infection, including

COVID-19.

The other study was conducted in Norway (BMJ, Sept. 7, 2022). The scientists recruited more than 34,000 people who were not taking vitamin D supplements. Half of them were given cod liver oil and the other half placebo, taken daily during the winter. Cod liver oil contains vitamin D (10 mcg or 400 IU per daily dose). These supplements did not reduce the participants’ chance of contracting

COVID-19 or other respiratory infection.

DREAMSTIME Some researchers say the recommendation of 8 ounces of water, eight times a day, is unscientific.