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Author Dr Ian Perry

In most modern aircraft flying long haul routes, the cabin pressure is maintained at around 5-6000ft (1500m) when the aircraft is flying at 37-41,000ft (10,000m). It’s something we give little thought to as we jet off but how does altitude affect the bodies of the 7 billion people who live at or around sea level. Of these 7 billion, 140 million live up mountains, in high places such as Quito, the capital of Ecuador which sits at 9,350ft (2,850m) high with a population of 2.67m people. Mexico City sits at 7,350ft (2,240m) with a larger population of 8.84 million.

All these inhabitants are acclimatised to living at such heights but when those who live at sea level visit one of these higher cities, we could initially find we feel breathless, faint, get a headache, become confused, make the wrong decisions, feel physically weak, have an accident or have disturbed bodily functions. But what causes this?

In simple terms, there’s less pressure of oxygen (O2) in the air the higher you go. Acclimatisation to this decreased oxygenation of the blood takes on average about 3-4 weeks. Mountain climbers take longer to acclimatise, with only a few managing to climb Mt Everest at 29,000ft (8,850m) without extra O2. This gradual preparation takes time; if not done carefully it can result in mountain sickness, requiring urgent medical treatment and O2.

The amount/concentration of O2 in normal air is 20.9%. The atmospheric pressure is the weight exerted by the mass of air all around us, and up to 50-60,000ft (15,250m). It is measured as one atmosphere at sea level. This atmospheric pressure gets less the higher up you go, so there is less pressure to drive the O2 gas through your lung membranes giving you the oxygenation that you require. Above 10-11,000 ft (3,000m), everyone has to breathe extra supplemental O2. At 18,000ft (5,500m), pressure has to be applied to any breathing equipment used by a pilot/mountaineer, to force the O2 into the blood stream in your lungs. In mountaineering above 18,000ft (5-5,000m) the altitude is known as the “Death Zone” as without supplemental O2 and the extra pressure, the majority of us not acclimatised, would obviously die. The early balloonists experienced these problems as they ventured higher and higher into the upper sky. Some died from oxygen lack.

As the human body goes higher, and gets less oxygen, the effects above 10,000ft (3,000m) can be very variable from person to person. You become “anoxic”, short of O2. The first sign can be a loss of colours in your vision.  The red cells in your blood carry the oxygen, on becoming deficient, the tissues throughout the body begin to suffer. The human eye is a very sensitive organ depending on oxygen to stimulate the light receptors at the back of the eye. These light receptors distinguish what colours you see. If there is a lack of oxygen, the light receptors cannot interpret colours, so a loss of colour vision can be an early sign of oxygen lack.  You can begin to feel aggressive, or sleepy. Speech can become slurred as you begin to speak nonsense as your words become jumbled. Someone writing who starts to become anoxic will lose the ability to put words and letters together. As the brain tissues begin to lose oxygen all the normal functions begin to falter. You may not be aware of these subtle changes until it is too late. In flying training most pilots undergo some form of experience in oxygen lack and its early signs. It is done formally in military pilots, in a decompression chamber.

This training is invaluable and has taught many pilots what to look out for and how to correct it.  As an aircraft passenger, the only risk is if the aircraft was to decompress, that is, to lose the cabin pressure. One of the standard drills performed by the cabin staff before all flights is to demonstrate to the passengers what to do if the pressure system fails. It is always to put on the oxygen mask first as you cannot help others until you are breathing normally, pulling on the gas tube to turn it on, making sure it fits snugly. There are control dials and switches at the pilots end to ensure steady cabin pressure at around 5-6000ft (1500m) when the aircraft is flying at 37-41,000ft (10,000m).

However, this can still cause some people to feel a little tight in the chest, even a little breathless. It is like being up a mountain of the same height, but it wears off as the flight continues. You get acclimatised, but it can take time, so no one should over exert themselves during a flight. You should also not make any cognitive decisions on the day of travel as your cognition will have been impaired travelling.


Author Shona Wilkinson 

Supplements simplified

Supplements are concentrated sources of nutrients or herbs that can be taken in addition to a healthy diet for increased nutrient intake. Sometimes they are in their natural food state, or they can be already converted into a more usable form. Supplements come in many forms including vitamins, minerals, fats, amino acids, herbs, enzymes and live bacteria. These can be used to ensure intake of important nutrients and other substances where the diet may be lacking.

Why do we need supplementation and a healthy diet?

In an ideal world, we’d be able to obtain all the nutrition we need from food. Even if we do eat relatively healthily, it’s hard to consume the optimal level of nutrients our body requires. Supplements provide a concentrated source of nutrients which we can consume in addition to a healthy diet to provide our body with vital substances that may otherwise be lacking.

Can the body make vitamins?

This is another common myth. Although your body makes many of the nutrients it needs to carry out its functions (known as non-essential nutrients), some nutrients can’t be made rapidly enough, or at all, to meet daily needs (these are called essential nutrients). They must be obtained from outside sources such as food or supplements. 

Whereas the body can create vitamin D (from sunlight) and vitamin A (from consuming enough orange coloured vegetables) it can’t produce the nutrients; Omega 3 essential fatty acids, B vitamins, Vitamin C and E, as well minerals.

Two forms exist, ‘fat soluble vitamins’ including A, D, E and K and ‘water’ soluble vitamins, including C and B complex vitamins. In addition, your body needs minerals to regulate itself which it can’t produce. There are 16 essential minerals that optimum nutrition requires. Firstly, ‘macro minerals’; sodium, potassium, chloride, calcium, phosphorous, magnesium and sulfur, are needed in larger amounts by the body. Secondly ‘trace minerals’; Iron, Zinc, selenium, copper, fluoride, chromium, molybdenum and manganese are needed in smaller amounts.

Nutrition is the foundation for the creation of new cells and hormones in the body and your body can only use what you give it. Not only are you a result of what you eat but also what you absorb.

It is especially hard to eat well when you are on the road. It is not always easy to get freshly made organic foods bursting with nutrition. Sometimes we are left with no choice but to consume food with questionable nutrition content such as packaged, ready-made or processed plane food.

5 great advantage of taking supplements:

1. We're easily able to manipulate our nutrient intake, knowing exactly how much we are taking, however supplements should obviously not be offered in place of food,

2. We can use nutrients in isolation for a specific reason which is impossible to do when relying solely on food,

3. We can take a larger dose of a nutrient without having to eat a meal - some supplements are suitable for taking on an empty stomach, 

4. They are compact, allowing us the flexibility to carry them in our bag rather than the original food source e.g. one dose of Vitamin C, 125mg provides the same amount of Vitamin C as in 5 oranges. Few would want to carry 5 oranges let alone eat them at once,

5. You can carry supplements through airports and abroad when you may not be able to transport therapeutic foods. Not many countries let you take food across the border. How do we know the quality of the food we may find on the other side?  

Finding quality

Not all supplements are equal. There is a massive difference in the way they are produced, and the nutrient forms used. Some lower quality supplements may provide nutrients in less absorbable forms which have lower efficacy. Whereas, premium quality supplements provide nutrients that are most useful to the body and easily absorbed, as well as guaranteeing the nutrient quality at the end of the shelf life.

Maintaining a healthy diet is considered one of the most challenging aspects of traveling. To maintain your body from the side effects of travel, your body needs to absorb all the nutrients it needs from a combination of nutrition and supplementation.

Maintaining a healthy diet is considered one of the most challenging aspects of traveling. To maintain your body from the side effects of travel, your body needs to absorb all the nutrients it needs from a combination of nutrition and supplementation.

Which supplements should I be aware of when traveling?

Sometimes our immune system requires more support than at other times, such as traveling to new environments. Supplements containing nutrients such as Vitamin C, D and Zinc contribute to the normal function of the immune system. Certain nutrients can contribute to a reduction in tiredness and fatigue such as B Vitamins, Magnesium and Vitamin C. 


Author Shona Wilkinson 

Zinc is an essential nutrient required for over 200 enzymatic process within the body. The body doesn't produce or store Zinc which means it must be obtained from our diet  or supplementation. Of all the trace minerals, this element is second only to Iron in its concentration in the body. Zinc is found throughout our body, in our cells, tissues, and organs; but most of the Zinc in the average adult body is contained in our muscles and bones.

Food Sources of Zinc

Zinc is generally found in protein sources such as red meat, poultry (darker meat areas), eggs and seafood. Vegetarians can obtain Zinc from eggs, cheese, beans, pumpkin seeds, grains and nuts, although Zinc is not as easily absorbed through non-animal sources.

What does Zinc do and why is it so important?

Zinc plays many vital roles in our body. The key functions are:

Our Immune system - Zinc contributes to the normal function of the immune system. Our bodies need Zinc to activate T cells, (lymphocytes that regulate our immune system and attack infected or cancerous cells).

Our Hair, skin and nails - Zinc also contributes to the maintenance of normal skin, hair and nails.

Our Vision and cognitive function - Zinc contributes to the maintenance of normal vision and normal cognitive function.

Our Cell division and cell protection - Zinc has a role in the process of cell division and contributes to the protection of cells from oxidative stress.

Zinc - the frequent flyers best friend

Frequent travelling can be stressful, both physically and mentally. Traveling to exciting and exotic destinations across the world, eating fast and processed food at unusual times and lack of restorative rest can all cause us problems.  Our bodies can be quite resilient but we need to take care of it as much as possible.

How much Zinc do I need?

The NRV (Nutrient Reference Value) for Zinc is 10mg. (The NRV is a straight replacement of the RDA Recommended Daily Allowance). 

We only ever use the best absorbed forms of Zinc in our blends. We only use the best forms of Zinc for the health condition area we are benefitting. Zinc Picolinate is used in our Immune Function blend whilst Zinc Bisglycinate is included in our Rest Function blend. The different forms of Zinc work in slightly different ways. Whilst the difference is minimal, the finest details are important to ensure you experience the best possible products.