The “Food Babe” is an excellent object lesson in why people who are not qualified should not be dispensing advice to the public. Spouting uninformed opinions is one thing, but presenting information in an authoritative manner as if from an expert should not be attempted by the non-expert.

If you want to dispense useful information on your blog or website (not just opinion) then it is appropriate to cite credible sources and experts and to accurately convey their information. “These are the facts concerning flu vaccines, according to the CDC,” then quote the CDC directly, with a link to the source.

Unfortunately the web is cluttered with people who really have no idea what they are talking about giving advice as if it were authoritative, and often that advice is colored by either an ideological agenda or a commercial interest. The Food Babe is now the poster child for this phenomenon.

She recently published advice for healthy traveling. The page has since been deleted, apparently in response to criticism, but it is cached here. The FB’s advice contains some real howlers, demonstrating that she lacks even the most basic scientific literacy.

She writes:

When your body is in the air, at a seriously high altitude, your body under goes some serious pressure. Just think about it – Airplanes thrive in places we don’t. You are traveling in a pressurized cabin, and when your body is pressurized, it gets really compressed! Compression leads to all sorts of issues. First off your body’s digestive organs start to shrink, taxing your ability to digest large quantities of food. Secondly, this compression reduces the ability for your body to normally circulate blood through your blood vessels.

FB apparently thinks that pressurized cabins are pressurized to greater than one atmosphere of pressure, or pressure at sea level. In reality, most jets are pressurized to between 6-8,000 ft, (Boeing says their cabins are pressurized to between 5,400-7,000 ft.) which is less than the pressure at ground level, but much higher than the outside pressure at typical cruising altitudes of 35,000 ft. Air and Space magazine explains:

On the ground, the airplane is unpressurized and the outflow valve is wide open. During preflight, the pilot sets the cruise altitude on a cabin pressure controller. As soon as the weight is off the main wheels at takeoff, the outflow valve begins to close and the cabin starts to pressurize. The airplane may be climbing at thousands of feet per minute, but inside the cabin, the rate of “climb” is approximately what you might experience driving up a hill. It might take an average airliner about 20 minutes to reach a cruise altitude of, say, 35,000 feet, at which point the pressurization system might maintain the cabin at the pressure you’d experience at 7,000 feet: about 11 pounds per square inch. Your ears may pop, but the effect is mild because the climb rate is only 350 feet per minute. When the airplane descends, the pilot sets the system controller to the altitude of the destination airport, and the process works in reverse.

This lower pressure may cause some discomfort in your middle ear, depending on how efficiently your ears equalize the pressure. Swallowing helps, and some people chew gum or have a drink handy to help this process. If you have a cold and congestion, equalizing pressure may be more difficult, and therefore using a decongestant prior to flight may be useful.

The lower pressure also does contribute to water loss and therefore dehydration. FB does correctly state that it is important to keep well-hydrated during flights, especially long flights. Cabins are kept very dry. FB says 10% humidity. One source I found says 12% (not a significant difference). the World Health Organization reports cabin humidity is usually <20%. One study of intercontinental flights found the average humidity was 5%. By comparison, home and office humidity is usually around 30%, but can be lower when heating is being used.

The dryness is a source of concern, and can lead to dry eyes, skin, and mucous membranes, as well as dehydration. Travelers with special medical conditions should consult their physician prior to travel if they are unsure how to compensate for the dry environment. Having moisturizer, lip balm, and access to fluids on long flights is helpful. You may also want to remove your contacts.

Incidentally, the reason for the dry air is that at high altitude the air is very dry, and humidifying the air would be expensive and impractical.

Regarding air quality, FB has this to say:

The air you are breathing on an airplane is recycled from directly outside of your window. That means you are breathing everything that the airplanes gives off and is flying through. The air that is pumped in isn’t pure oxygen either, it’s mixed with nitrogen, sometimes almost at 50%. To pump a greater amount of oxygen in costs money in terms of fuel and the airlines know this! The nitrogen may affect the times and dosages of medications, make you feel bloated and cause your ankles and joints swell.

I have no idea what she is talking about here. First, air is partly recirculated and partly pumped in from the outside. The outside air at 35,000 feet is cold and dry, but otherwise is likely fairly clear. Air in the cabin is completely replaced every 2-3 minutes. It is also highly filtered, removing between 97-99.9% of the germs and other large particles in the air. The air quality is likely better (other than the dryness) than your average office or movie theater.

FB seems distressed that the air that is being pumped in isn’t pure oxygen. It’s a darn good thing it isn’t. Perhaps she is not familiar with the Apollo 1 disaster – pure oxygen atmospheres are fire hazards.

She also is concerned that the air may contain up to 50% nitrogen. She is apparently unaware that the earth’s atmosphere is 78% nitrogen, 21% oxygen, and 1% CO2 and other gases. Yet according to FB’s bizarro world the evil airlines are contaminating our pure oxygen with 50% nitrogen to save money.

Here is some classic FB fearmongering.

Did you know certain countries require that airplanes and even passengers be sprayed with pesticide before they take off? This means if you are visiting one of these countries you are breathing in these fumes potentially all flight, especially if they were sprayed on board. Horrific!

While this is true, it is somewhat less than “horrific.” The WHO reports that international law requires that flights from countries that carry insect-born diseases, like malaria, disinfect their cabins to prevent the spread of those diseases through air travel.

Procedures may include spraying the cabin with insecticide between flights, prior to passengers boarding, or even after passengers have boarded but prior to takeoff. They report:

Passengers are sometimes concerned about their exposure to insecticide sprays during air travel, and some have reported feeling unwell after spraying of aircraft for disinsection. However, WHO has found no evidence that the specified insecticide sprays are harmful to human health when used as recommended.

The most commonly used insecticide for this purpose is permethrin. This has been used for years, is used in insect repellent meant to be sprayed on the skin, and is also impregnated into clothing to help prevent insect bites as disease vectors.

There is some legitimate controversy over the risk-benefit of spraying insecticide in cabins, mostly for the airline crew who are exposed daily. Non-chemical means of disinsecting cabins are being explored. The US also now requires passengers to be informed when insecticide is being used.

Here are FB’s specific recommendations for in-flight health and safety:

1- Drink 8 ounces of water for every hour of flying time

2- If you experience a headache, pains or aches, think about using turmeric, garlic or willow bark which are all natural alternatives to aspirin

3- Fast or eat small light carbohydrate rich whole foods.

4- Limit any heavy dairy or protein rich foods.

5- Whole grain carbohydrates are better tolerated than proteins at a high altitude.

6- Do not drink alcohol or caffeine on long flights

7- Walk or stretch every 30 mins while in flight, if you can’t get up from your seat, rotate your ankles and raise your arms over your head to stretch

8- Keep your hands clean with natural hand sanitizer spray and avoid touching your face as much as possible

9- Don’t forget to take your natural herbs that can strengthen your immune system

Her recommendations are a combination of common sense and widely known advice and outright BS. Let’s go down the list:

1 – While it is a good idea to bring fluid and keep well hydrated, the 8oz per hour is simply made up. You may need more or less depending on conditions.

2 – Why not use aspirin? This is purified, has a known dose, no contaminants, and is very safe.

3 – Baseless recommendation without evidence.

4 – Baseless recommendation without evidence.

5 – Baseless recommendation without evidence.

6 – This one is reasonable, and you will find the same advice from airlines and travel resources.

7 – This one is reasonable, and you will find the same advice from airlines and travel resources. Again, the “every 30 minutes” is oddly specific, without a reference, but it gives the impression of being evidence-based.

8 – This is generically true whenever in crowds. However, as I stated above, the airplane itself is not a particularly germ-ridden environment, is is likely less so than many other crowded locations.

9 – There are no herbs that strengthen your immune system, so this one is pure nonsense. In fact, it may give people a false sense of security.

Conclusion

The Food Babe is shockingly scientifically illiterate and should not be giving advice to anyone. She is not an expert. She does not seem to have any respect for expert opinion or carefully sourced information. Her advice is a crap shoot of common knowledge, fearmongering, gross scientific illiteracy, misinformation, and ideological nonsense.