Vit A is needed for the integrity and defence of our skin and the mucous membranes that line our mouth, nose, gut and lungs. Without this we are vulnerable to attack by viruses and other microorganisms.

There are tiny hair like projection in the windpipe called cilia that waft any particles we have breathed in up and out of the lungs. They too depend on vitamin A. Some viruses enter the body through the surface of the eye. Vit A helps to lubricate it and defend it from infection.

It is essential in the formation of mucus, again a protective layer, against attack by germs. It also plays a role inside the body supporting our immune system. It is needed for our immediate response to invaders. White cell such as neutrophils and macrophages are our front line troops that instantly go after what is recognized as foreign.

Real vitamin A is called retinol. This is only available from animal foods. The richest sources are liver, eggs, cod liver oil and high fat dairy. It is a fat soluble vitamin and is best absorbed with fat.

Many people think that carrots are a good source of vit A and that they help with night vision. Indeed there are about 600 compounds called carotenoids, named after carrots, that can undergo conversion by the body to vit A. These compounds are termed pro-vitamin A. In some individuals this conversion is poor. In about 25% of the population have a marked reduction in the ability to convert the carotenoids to real vit A. Is it worth the risk? Carotenoids are not an essential food as a result.

How much do I need?

4 oz of ideally liver from pastured or grass fed animals per week. Pate is a great food made from liver and butter – both good sources of vit A.

3 eggs a day from pastured chickens.

3 servings of full fat dairy from grass fed animals. Butter from grass fed cows is great.

1 teaspoon of cod liver oil.

Lascaux, a cave in France, is World famous for its ancient art. The artists painted the chambers with aurochs a very old version of the cow. There is a Hall of the Bulls with striking images of these creatures that were far more aggressive than our modern domesticated version. They date between 15-17,000 years ago. Humans were alive in the paleolithic or stone age far longer than our recorded history. At that time humans had been in Europe for tens of thousands of years. Many animals would have been much bigger than today, the so called megafauna. There were huge bears, lions (yes in Europe!), the huge Irish elk, wooly mammoth and rhinos. We were both hunters and hunted.

The cave was discovered by accident by four boys. Their dog, called Robot, fell into a rabbit hole that lead to the chambers. It was one of the greatest discoveries of ancient paintings of the 20th century. Millions of people visited the cave. The fungal spores in their breath along with the change of environment has devastated the images. As a result a reproduction of the cave is open to visitors.

What do these paintings mean? They do not depict plants or the landscape but man and animals. What can we learn about the spirituality of these early Europeans? Prof Marcel Otte from the University of Liege is probably the World expert in this area. It seems likely that they were animists. That is believing that there are spirits in animals, trees and some inanimate objects.

We now know that Neanderthals were way more sophisticated than we thought. Both they and Homo Sapiens practiced burial of the dead. Could they have believed in an afterlife? Or did they worship their ancestors? This strange World separated from us by a chasm of time remains lost and mysterious.

Dry eyes are a common symptom in our screen obsessed times. Some medications such as antihistamines and common psychiatric medications can provoke it. There are also autoimmune conditions such as systemic lupus and rheumatoid arthritis that are also associated.

A big reason is screen time. The eye does not move and we are not stimulated enough to blink regularly. Your doctor can detect it using a dye called fluorescein that in health should spread evenly across the eye. It is patchy when the eye is dry. The eyes have sebaceous glands like the skin that produce an oily film that stabilizes our tears. These glands are the meibomian glands and they reside in the inner lids. They can get clogged and present as firm lumps. An ophthalmologist can reduce these using a simple technique. This does not deal with the underlying causes. As dry eye progresses more and more of the glands are lost. When they are gone they cannot be revived and the patient is left with a permanent dry eye.

Industrial seed oils are best avoided as they do not contain the fat soluble vitamins that the eye needs such as vit A. Traditional animal fats provide the meibomian glands the right nutrients to form the oily layer that prevent the tearfilm evaporating.

Please avoid artificial tears that contain polyvinyl alcohol. This is toxic to the eye and best avoided. A LipiScan shows the eye doctor how badly the glands are damaged. Lipiflow is a thermal and pressure treatment done in the doctor’s office, takes 12 minutes and can give symptomatic relief for 2-3 years.

If you cannot access this then a hot compress to the eyes every day and blinking hard afterwards can also be effective. Avoiding vents and using a table top humidifier can also help.

One of the few useful discoveries of the research called the Women’s Health Initiative is that those would ate oily fish 2-3 times a week had less dry eye. Supplements of omega 3 long chain fatty acids, DHA, EPA and GLA have had mixed results. So enjoy salmon, anchovies, mackerel, sardines and herring.