I, like most Americans, love salt. My ethnic culinary background has made salt a very traditional condiment. (Think chicken soup, koshered fowl, pickles, smoked white fish, hummus, pitas…then add on American potato chips, processed meats, breads, cookies, sauces and salad dressings). I was going to have a string cheese as a snack while I wrote this….but I looked at the wrapper and it contains 210 mg of sodium (remember sodium chloride is salt). And since a quarter of a teaspoon of simple salt is 1.5 gram or 590 mg of sodium, I guess I also won’t salt those carrot sticks.

An article appeared this February in The New England Journal of Medicine that was titled “Compelling Evidence for Public Health Action to Reduce Salt Intake”. Their projections were astonishing. The authors, from The University of California, San Francisco, used a computer program called the Coronary Heart Disease Policy Model to quantify the benefits of reducing dietary salt by 3 grams a day (or in sodium terms, and that’s what you find on food labels… 1200 mg of sodium per day). This reduction would have a tremendous effect, reducing the annual number of new cases of coronary heart disease (CHD) in the U.S. by 60,000 to 120,000, stroke by 32,000 to 60,000 and heart attack by 54,000 to 99,000 and reduce the annual number of deaths from any cause by 44,000 to 92,000. (And, for the mostly women readers of my website…please note that the projected reductions in stroke would be greater among women than men.) All this could save $10 billion to $24 billion in health care costs annually!

In short, salt reduction would be as beneficial as interventions that reduced smoking in the US by 50%, a 5% body mass reduction in all obese adults or the use of drug therapy for people with hypertension and hyper cholesterol levels. Moreover it is probably as important as reducing trans fats in all foods and increasing our consumption of fruits and vegetables. The authors of a commentary in the same issue also point out that salt reduction may reduce risk of gastric cancer, kidney disease, congestive heart failure and osteoporosis.

It turns out that we are a population of salt eaters ….consuming more than in many other developed countries. Although the current guideline for salt consumption by The Departments of Agriculture and Health and Human Services is less than 5.8 g of salt (2300 mg of sodium) with a lower target of 3.7 g of salt per day for persons over 40, blacks and persons with hypertension; the average man in the U.S. consumes 10.6 g of salt per day and the average woman 7.3g per day. And statistics have shown that the amount of salt we consume is on the rise.

So what can we do? Certainly look at labels.  Seventy-five percent to 80% of the salt in the U.S. diet comes from processed foods. Our government (doesn’t it always seem to come back to them) should probably begin a program of regulations on the salt content of processed food, make labeling clearer and work with the food industry to reduce salt….it worked for trans fats. And it behooves us, the consumers, to look at those labels, choose less salty alternatives (begin with cans of soup and breads and hey potato chips and pickles may have to go) and of course start using foods that are not processed. (Well at least try in some areas of food preparation….it may be difficult for most of us to bake all our breads or raise our own fowl and meat.)  And let’s not forget to diminish the salt intake of children. Between their processed snacks, cereals and the children meals at takeout and eat –in restaurants they are being inundated with salt.  Hypertension and plaque build up starts at a very young age as does the preference for salt.

Studies have shown that as salt intake is reduced, children and adults prefer food with less salt. Our taste receptors change over the course of just weeks or a few months. Taste is an acquired sense that can be changed. I for one will try to continue to enjoy what I eat sans excessive salt. (There goes the salt rim on the Margarita glass, oh well….)

One last encouraging note; the article pointed out that even if there was a more modest reduction in our salt intake by as little as 1 g a day there would be a significant projected decline in the annual rates of cardiovascular events and deaths. So if you can’t go salt free try for salt “freer”

I have been mesmerized by the Winter Olympics. Each night, I eagerly tune into the NBC broadcast and watch with amazement as snowboarders and skiers race, soar and somersault in defiance of gravity, human speed and most probably their mothers. I know the latter are in the crowds cheering their progeny on…How do they do it? Do they have to avert their eyes as their progeny perform impossible feats? Needless to say, I am not the mother of an elite athlete. When my younger daughter competed in gymnastics, I would avoid watching her high beam practice and/or events. Indeed, I was not terribly unhappy when she decided to stop her training at the age of 12!

So while entertaining thoughts of injury, I was rather pleased to find a commentary titled “Skiers, Snowboarders, and Safety Helmets” in this week’s JAMA. The authors cited some statistics that A) verified my concern and B) addressed ways to appease them. Apparently there are 600,000 ski-and snowboard-related injuries each year. Of these, an estimated 15% to 20% are traumatic brain injuries and are the leading cause of hospitalization. Head and brain injuries account for 50% to 88% of total deaths in skiers and snowboarders. The US Consumer Product Safety Commission estimates that 44% of head injuries could be prevented by use of helmets and that 53% of these injuries in children would be reduced by strapping the appropriate helmet on their heads. Other studies have been even more “helmet praiseworthy” citing a 60% reduction in head injuries. They have also found that their use does not appear associated with an increase in spine or neck injury.

Despite this, the authors then give the rather astonishing stat that in a recent study at a western New York ski resort only 37% of 1472 children wore a helmet while skiing and snowboarding. Other studies have found that only 12% of the general ski and snowboard population wear them.

Fashion may have been the issue, but the Olympics will, I hope, change that. The helmets the competitors wore looked fabulous….remember the gold one, or how about the new fashion for women of “stick out” pigtails?
It would also help if ski patrols at resorts wore helmets regularly.

Bottom line: Having the wind in your hair may feel great, but not if you are attempting to traverse the surface of snow with skis or a snowboard at any speed. And as you pay those fees for ski and snowboarding lessons and equipment for your kids, make sure that a helmet (in any color they want) is included and always used.

We all want that something, preferably an over-the-counter and inexpensive pill, to help maintain our memory, acuity, ability to process information (like medical newsletters) and our daily mental activities. I have to admit that several years ago I took Ginkgo biloba and indeed, if I forgot my daily dose, worried that I would be unable to complete a section in one of my books.

So it was with disappointment that I read the results of the Ginkgo Evaluation of Memory (GEM) study, the largest completed randomized double-blind dementia prevention study trial that was published in JAMA in 2008. It found that when Ginkgo biloba was taken at a dose of 120 mg twice daily, it was not effective in reducing the incidence of Alzheimer dementia or overall dementia. But there was still some hope that perhaps this herb which has been thought to work by dilating blood vessels in the brain, reducing free radicals or even reducing the viscosity of the blood flowing through the brain could slow the age associated decline in cognition in those of us who started out without symptoms, i.e. were cognitively OK.

The researchers of the GEM study recently finished tabulating results that could answer this premise…and came up with disappointingly negative conclusions. They followed 3069 participants aged 72 to 96 who had normal cognition. They were either given twice-daily doses of 120-mg extract of Ginkgo biloba or an identical appearing placebo for an average of 6 years. Each year they tested their memory, attention, visual spatial abilities, language abilities and executive functions (yes there are tests for this). They found that the rate of change varied according to how well these individuals did initially.  (If they started out with lower scores they ended up with even lower ones). But there was no difference in rates of change between treatment groups. Age, sex, race, education or baseline cognitive impairment did not modify the effect of the treatment. (In other words, G. bilboa did not work better or make a difference in rates of decline for men, women, older, younger or better educated individuals.)

Bottom line: This herb does not work to stave off cognitive decline in older adults. Whether it helps a younger person do so is doubtful. I stopped my Ginkgo years ago and no longer feel guilty.

This is probably a great opportunity to repeat the adage “what is good for the heart is good for the brain”: So exercise (your body and brain), eat a healthy diet, don’t gain weight and make sure your lipid levels are not elevated. Save the money you might spend on Ginkgo supplements for great exercise shoes!

I have just returned from Israel. Ten time zones and a 15 hour (if it’s non-stop) flight will guarantee jet lag. So please forgive me if this piece is somewhat disjointed. The El Al flights I took were uneventful and indeed I slept most of the way. But as I landed in LA my ear painfully popped, I started coughing and sneezing, had a sore throat and generally felt awful.  I was reminded of a segment that I had done for the Today Show titled “Microbes on a Plane”. (It was supposed to be a take-off on that awful movie “Snakes on a Plane”.) Thankfully, after judicious but liberal use of antihistamines, anti cough medicines, lozenges and anti rhinitis nasal sprays I feel better (but am still jet lagged). Did I get sick from my plane ride? Probably not.  More likely I acquired a viral infection while visiting my family and friends (and spending time in several hospitals, a university and a nursery school).

Having just gone through this I felt it would be appropriate (and easy) to share what I wrote for the Today Show in this week’s newsletter. I assume that you will be reading this at home or in your office and not on a plane….

Which diseases are most likely transmitted through cabin air?

  • The common cold. Believe it or not, there are very few published reports of cold outbreaks as a result of air travel. That may be due to the fact that colds are so common that it’s difficult to compute whether they were “caught” on a plane. Also the decrease in the humidity of airplane air with subsequent drying of nasal passages, fatigue and proximity to someone who is sneezing and coughing are variables that affect a person’s susceptibility and the likelihood of infection with cold viruses. But “infected” plane air is probably not to blame; a study of the percentage of fresh air, which was re-circulated in the cabin (50 percent versus 100 percent), showed that it made no difference in the development of upper respiratory tract infections. (This would not be the case, however, if the plane is on the ground, the doors are closed and the air system is shut off.)
  • Influenza (seasonal and H1N1). We know that air travel allows individuals from one area of the world to spread a specific type of flu to another and indeed, air travel is probably the chief cause of global spread. But there is less concern about actual in-flight transmission, unless the aircraft is grounded with an inadequate ventilation system. In that case, there have been documented outbreaks. The current recommendations require “that passengers be removed from an aircraft within thirty minutes of shutting off the ventilation system”. The best way to decrease your chances of infection is to get your flu shot, and remember, immunity occurs two weeks after the vaccine, so plan ahead. (By the way I had mine.

Other airborne “large droplet” diseases include:

  • Tuberculosis. This disease is global; one-third of the world’s population is currently infected. Studies since the mid-1990’s have documented in-flight TB transmission. The largest USA incident occurred when a passenger traveling on a trip from Baltimore to Honolulu infected four of fifteen passengers seated within the closest two rows (they didn’t all develop TB, but they did have positive TB skin tests). A risk analysis published in 2004 estimated that the overall probability of TB infection during a long air flight is around one in a thousand, when a person with TB symptoms is on the plane. This is similar or perhaps even less than the chance of becoming infected by a person with TB in other confined spaces.
  • SARS. This is transmitted by large airborne droplets or by direct contact. There has been substantial evidence that in 2003 during the SARS outbreak, transmission of the virus occurred through airplane air to passengers seated within five rows of the initially infected person and that the infection occurred on fairly short flights. (In one three-hour flight from Hong Kong to Beijing 22 of 120 passengers contracted SARS). Since then, the “epidemic” has dissipated and there have been no major outbreaks of concern.

What about food and water contamination?

Microorganisms that cause food poisoning and gastroenteritis diseases usually are spread by contamination of food or water. These include salmonella, staphylococcus, cholera and a virus called Norwalk-like agent. No food borne or water borne outbreaks have been reported over the past few years, probably because the food is so often pre-packaged and frozen.

The water in on-flight tanks, especially if filled from water sources which are less than “pure” may be contaminated. Long or repeated storage within the tank can, despite best efforts, result in bacterial growth.  If you don’t want to drink the water in the country from whence the flight originated, don’t drink the water from the plane tank. Bottled water is always the safest way to maintain hydration.

What about the dry air?

The humidity within the cabin is usually below 25 percent and can definitely cause sinus and mucous membrane discomfort. We would probably feel better if the humidity was 35% (that’s what it is in a comfortable home environment), but increasing humidity can also encourage growth of bacteria and fungi, especially in the aircraft water tanks; hence the airline industry has hesitated to do so.

So what can we do to stay healthy when we fly?

  • Respect others. Don’t fly if you are sick. Aside from concern for the other passengers’ health, flying with an ear, nose or sinus infection and/or severe congestion, may cause obstruction of airflow in your middle ear and sinuses during takeoff and landing. This in turn can cause severe ear and sinus pain and injury to the eardrum.
  • Prevent dehydration. Drink plenty of water (and make sure your children do this, they are especially susceptible to dehydration.) If you want to ensure that the water you drink is not contaminated, ask for bottled water. Don’t add ice cubes if they are made from water that could be unsafe. Drink tea and coffee only if the water used to make it is boiled or is bottled.
  • Limit caffeine and alcohol, these add to dehydration and jet lag.
  • Prevent dryness of your skin, eyes and airways. Use moisturizer, saline eye drops (or rewetting drops) for contact lenses and saline nasal sprays. (As I write this I’m aware of the restrictions on bringing these items on board the plane; I hope they will be reversed. You can always get a note form your doctor for the eye and nose drops.)
  • Practice good hand hygiene. Wash your hands before you eat. Don’t put your unwashed hands in your mouth or rub your eyes.
  • Move. If someone nearby seems sick, ask if you can move to another seat. And don’t forget, even if you are surrounded by healthy individuals, it’s important to get up, move and stretch to prevent blood clots and deep veined thrombosis (DVT).
  • Mask? The use of masks to prevent infection within the aircraft carrier is unproven.

Bottom Line: Work, recreation and families have become global. Most of us have to fly. With rare exceptions, we don’t risk serious illness. Simple hygiene, hydration and judgment can help prevent air related health problems.

New Bottom Line: Follow these rules, but know that lack of sleep, the stress of long distance travel and exposure to viruses and bacteria in distant places can result in illness. In my case it was blessedly brief. I plan to repeat this and many other trips. I know that immunity is not bestowed with a medical degree. I wish it were.