What is vitamin D?
First, a look at vitamin D. It's a vitamin we can get from our food or produce through the effect of sunlight on our skin. As food sources are fairly skimpy, and we don't all get a great deal of sunlight exposure, supplements have a role to play in ensuring we get sufficient doses. Once absorbed into the body, vitamin D is stored in the body's fat cells, where it lies inactive until it's required. Then, the liver and kidneys turn the stored vitamin D into the active form – calcitriol.
What is Echinacea?
The Echinacea species most researched for supporting immune function against respiratory tract viruses is Echinacea purpurea. A plant bees and butterflies love, it has been used for centuries for countering infections. Licensed by the Medicines and Healthcare product Regulatory Agency (the MHRA) in the UK, it is used for colds, flu, and upper respiratory tract infections. It is not used as a food, although non-medicinal teas are available, and is therefore taken as a supplement.
Vitamin D is an essential nutrient we can get from food or synthesise ourselves. Echinacea is a botanical remedy that is taken as a natural aid for immune function.
A.Vogel Immune Support Tablets with Vitamin D, Vitamin C and Zinc, 30 tablets
"Simply herbal. Very effective."
Read more customer reviews
What do vitamin D and Echinacea do for the immune system?
Both vitamin D and Echinacea have been found to protect against the common cold (which is mostly caused by viruses), and Echinacea was also indicated for treatment of infection.1
Vitamin D helps to activate immune cells when they need to respond to a threat.2,3 So, a lack of vitamin D will reduce the effectiveness with which your immune cells leap into action when an infection strikes.
There's some evidence that a better vitamin D profile will reduce inflammatory processes in the body.4 This in turn means there's less chance of a bad outcome when faced with infections such as SARS-CoV-2, which has been associated with extreme inflammation.
Echinacea has been shown to have direct antiviral and antibacterial effects against viruses and bacteria that cause respiratory tract infections such as colds and flu, as well as reducing infection-driven inflammation.5 In laboratory research, Echinacea has been shown to inactivate viruses such as SAR-CoV-1 and -2.6
As well as acting directly against a series of viruses, Echinacea has also been shown to support immune resistance.7
Vitamin D deficiency will reduce the efficiency of your immune response and increase levels of inflammation in your body.
Echinacea can support the effectiveness with which your body responds to infections, as well as directly killing viruses and bacteria.
When should I take vitamin D and Echinacea?
The interesting thing shown in the research quoted above,1 was that people benefited most from vitamin D supplementation when they were low in it to start with. This makes plenty of sense – correcting deficiencies is always beneficial. It also means that if your vitamin D levels are good already, you don't benefit from increasing them.
On the other hand, if you take high doses of vitamin D when you don't need it, you may overwhelm the storage facilities. The result can be an elevated level of calcium in the bloodstream, which isn't good for the heart or the kidneys. If you take some types of heart medication, too much vitamin D can raise the level of calcium in your blood and lead to an abnormal heart rhythm. Taking a little too much D when you don't need it is unlikely to cause problems, but high doses long-term are not advised.
(It's almost impossible to get too much vitamin D from the sun, by the way; but obviously it's not good for your skin to be exposed for too long.)
Echinacea is indicated if you want to support your immune system when faced with a cold or flu infection, and many people take it when they feel their immune response is not up to scratch. Research has shown that it is particularly useful for those who were prone to infections, were stressed, or poor sleepers, or smoked, factors that are all detrimental to good immune function.8
If you take Echinacea when you don't need it, it passes harmlessly from your body.
Should I take vitamin D or Echinacea for immune system support?
Take vitamin D if you know you are deficient in it. If you suspect you may be deficient, ask your doctor to check for you, and take a moderate dose until you get the results. It may also be worth topping up a little during the winter months or when stuck indoors out of the sun.
Take Echinacea to support your immune system when tackling infections. This is appropriate for most of us, especially as we start to come into contact with more cold and flu infections this spring.