If you’ve ever taken a vitamin C tablet thinking it will stop you getting a cold, you’ve bought into the myth of immune boosters
Go to any pharmacy, supermarket, or health food store in New Zealand and you will be find a sizable section of pills, powders, and potions with labels claiming that their product “may help support immune function” or “enhances winter wellness.” These are generally marketed under the label of ‘immune boosters’. Specific illnesses are rarely mentioned: instead you see virtually meaningless phrases like “helps keep winter ills and chills away”. The main ingredients that are touted as helping build an immunity against colds are vitamin C, echinacea, bovine colostrum, and propolis or royal jelly. But can you really boost your immune system by taking these products? I asked Dr Joanna Kirman, an immunologist who specialises in applied, cellular and molecular immunology, medical microbiology, and vaccine immunology and technology.
“When someone talks about boosting the immune system, it’s not clear what they mean,” Dr Kirman told me. “There are so many different cells that are working together. What cell are you boosting? Boosting some cells is going to be relevant, and boosting other cells is going to be irrelevant. It depends on the type of infection and the context.”
If you look at any kind of product that is approved as a medicinal product, they will always include product information sheets with them, and they will reference the work that they’ve done - the peer reviewed studies that they have conducted - to show that their particular product works. Medicinal products also list effects, side effects, and how long and in what quantity it is safe to take.
We develop immunity to viruses through exposure to them. Dr Kirman showed me a video demonstrating how the immune system works. It is a fascinating and beautiful process, complex almost beyond belief. When you get an infection, your immune cells are activated and start to produce molecules that can fight the infection. Some of what you experience as symptoms is your immune system fighting. Snot, for example, is your body’s response to an infection. Mucus traps a lot of microbes and we’re able to cough that mucus out. It's disgusting but is beneficial to us. It can contain molecules that are antiviral and antibacterial. Even though we hate mucus, it is our friend. Same with vomiting and diarrhoea. It’s your body’s way of getting rid of pathogens.
An over-active immune system can make you very sick, so do we want to boost it at all? “It really depends,” says Dr Kirman. “There are a lot of disorders that are created by your immune systems - asthma, allergies, rheumatoid arthritis - lots of diseases where amping up your inflammatory responses might not be a good idea.”
I photographed a range of ‘immune-boosting’ products to show Dr Kirman. Good Health’s ‘Immulox’ claims on the package to support healthy immune function AND help balance an overactive immune system. It says they are “Passionate about quality and effectiveness” and they have a circle saying “effectiveness” with a big tick. Dr Kirman said “people can put a big tick on anything”.
The FDA in the US makes products label themselves as non-medicines. A US ‘immune boosting’ product I found has on the label: “This product is not intended to diagnose, treat, cure, or prevent and disease.” Products from New Zealand are not required to have similar labels. Here are some things to look out for:
Vitamin C
Most of us have taken vitamin C in the hopes that it will prevent or help cure the common cold at some point in our lives. And it truly is a cure – for scurvy. The idea that vitamin C prevents colds came from Linus Pauling, a brilliant American chemist who won Nobel prizes in both science and peace. He teamed up with “Doctor” (term used loosely) Irwin Stone, who told Pauling that he could live another 30 years if he took 3000mg of vitamin C every day. In 1971, Pauling wrote a book called Vitamin C and the Common Cold, and it sold like crazy. He believed that taking massive doses of vitamin C could both cure a cold and prevent you from getting it in the first place.
There are around 2000 published studies a year on the effects of vitamin C on the human body. The vast majority of these studies show that taking large amounts of vitamin C is at best pointless, and at worst dangerous. Since our bodies cannot store it, most excess vitamin C you ingest will be excreted in your urine.
Dr Kirman said that if you’re eating a healthy diet, you don’t need to take vitamin C tablets, and “if you take too much you get diarrhoea”. It is hard to overdose on vitamin C unless you’re taking massive amounts, as you will expel excess in your urine. “If you’re eating fruit during winter, taking vitamin C probably won’t do you any good either. If you’re going to spend your money, spend it on fruit.”
Another thing Dr Kirman pointed out is that “immune boosting” vitamin C tends to be incredibly expensive, especially when mixed with other, more exotic-sounding substances. If you really want to take vitamin C, you can buy it very cheaply and it will be exactly the same as the $40 stuff.
Bovine Colostrum
Colostrum is a fluid that female mammals produce from their mammary glands after they give birth. It’s a clear, yellowish substance that will be the newborn baby’s first meal. As well as nutrients for the baby, colostrum contains antibodies produced by the mother animal that she will pass on to her baby.
Antibodies are cells made by the immune system that recognise certain alien cells, such as bacterium, and attach themselves to them. Once attached, the antibody makes it impossible for the foreign pathogen to enter the cells of its host, and so prevents infection. Each different pathogen requires a unique antibody to attach to it, so the prototype or pattern antibody cell is stored in the lymph node, where it can duplicate itself and send out an army of defensive antibodies to fight the invasion. By passing antibodies on to her baby via her colostrum, the mother mammal is giving her baby’s immune system the information it needs to help fight the bacteria and viruses her baby may be exposed to.
Colostrum is a wonderful thing and the reason why new mothers are encouraged to breastfeed their babies if they can. It seems like it would make sense for us to collect the colostrum from other animals and eat it in order to gain their antibodies and strengthen our immune system (as long as you don’t think of the baby animals missing out). Colostrum pills cost around a dollar each. They are touted as beneficial to the human immune system.
Dr Kirman told me why eating colostrum pills might not be a good idea. Antibodies are labile, which means they have a delicate, frill-like structure that is easily damaged. Though they can survive going through a baby’s digestive system and into the blood, they are unlikely to remain intact after being extracted, dried, and put into a pill. Doctors sometimes prescribe antibodies, but it is administered intravenously, not in pill form.
Even if the antibodies remain functional within the pills, it is unlikely that the antibodies the animal has made will be useful for fighting pathogens humans are exposed to.
The pack I found boasted having polypedtides - “tiny signalling information carriers known for their advanced immune balancing function”. Dr Kirman said: “A polypeptide is just a protein. It sounds fancier if you write polypeptides. Peptides are the building blocks of protein, so if you have a string of peptides, you make a protein. I don’t understand why a prolene rich peptide would be immune boosting.”
Animals catch different diseases to us. Save your money and leave the colostrum for newborn babies.
Royal Jelly
Another food for newborns - royal jelly is a secretion made by honeybees used to feed newly hatched larvae. If a female larva is fed huge amounts of royal jelly she will turn into a queen bee, and nurse bees will continue to feed her on jelly for her whole life. Queen bees are much larger than other bees, and their lifespans are much longer. Bottles of royal jelly pills are around $50-100.
“Promotes energy and vitality. Supports a healthy immune system,” reads one bottle. Good Health’s “Bee Vibrant” royal jelly costs $89.99 for 100 capsules. It emphasises that “Royal jelly is good for making queen bees” and that it “Extends her lifespan”. “Will that make us live longer?” asks Dr Kirman. “Are we bees?” “These things say they boost your immune system and they have no clinical data that supports that. They’re hugely expensive.”
Echinacea
Echinacea is a plant with strange looking flowers that is used in some traditional medicine. The Journal of the American Medical Association (JAMA) has looked at 24 trials and studies that were conducted between 1990 and 2010.
The bottom line of the collected studies shows no association with prevention of the common cold, though exploratory meta analysis suggests echinacea may be associated with a small reduction in cold incidence. Treatment trials have shown no association between echinacea and a reduction in cold symptoms.
Dr Kirman also told me that the dose of echinacea probably varies enormously between different products. If the packaging doesn’t tell you, you have no way of knowing the concentration of the supplement, the species of plant, or what part of the plant you are ingesting. Is it the flower, the leaves, or the roots? We looked at Nutralife’s Ester-C, which contained vitamin C, echinacea, and vitamin D3 and offered “24 hour immune support”. It retails at $59.99 for 120 capsules. Dr Kirman said that “24 hour immune support” appears to be “completely unsupported by anything – except that they want you to take it in another 24 hours”.
What to do
Lumping colds and flus together as ‘winter ills and chills’ minimises how serious they can be, especially influenza. “Flu’s not minor. The cold is generally minor if you’re otherwise healthy, but a flu, absolutely not. It can be deadly. And a cold in individuals who are immunosuppressed, really small children, and the elderly, can be dangerous. They can get secondary infections after a cold. Colds are caused by a huge range of different viruses, flu is by influenza viruses. They are very, very different illnesses.”
So what should you do to prevent the spread of viruses? Dr Kirman says, “What I would spend my money on is getting a flu vaccine. It specifically boosts your immune system to the flu. It creates those antibodies against specific strains to the flu. If you encounter that strain of flu, hopefully the antibodies will mop it up before you even show signs of infection. Sometimes you will get the infection, but it will be a milder infection than you would have had without.” Even if you haven’t had influenza before, getting a flu shot helps protect vulnerable people who can’t get the vaccine themselves.
Colds are spread through droplets, usually via people’s hands. To prevent colds, wash your hands thoroughly and regularly and avoid touching your face and ears. There are some products available over the counter that have some scientific backing behind them. Decongestants and painkillers can help ease the misery of a cold.
Dr Kirman’s own research group is looking at acute respiratory infection in childhood. Vitamin D was one of the things they looked at. The study is called “Whiti Te Ra” - let the sun shine. There is a school of thought that low vitamin D levels could be associated with decreased immunity and susceptibility to infection. “It’s a very weird kind of thing. Production of vitamin D in our bodies is stimulated by sunlight (UVB radiation). In winter there’s reduced daylight hours, it’s freezing, and the sun is a lot lower in the sky so you don’t get the same level of UVB exposure.”
What’s the harm?
I wrote this feature to hopefully stop students wasting money on products that probably do nothing, but Dr Kirman says there may be another reason to avoid taking immune boosters.
She says that though these products are not regulated, they can have side effects. “A good example of that is St John’s Wort, which can have quite significant side effects. It can affect the metabolism of some drugs.” It’s important for people who are taking anything over-the-counter to know what they are taking, so that if they do get sick they can tell the doctor. “It’s no good to say, ‘I’m taking Blackmore’s Immune Booster.’ They, like me, will have no idea what’s inside that. You can get drug interactions.”
If you have been taking immune boosters and swear they make you feel better, you could be right. The placebo effect is real. “One thing I can tell you that is really, really strong and quite amazing is the psychological effect of taking these things.” Weirdest of all, as medicines have become more effective, people’s expectations have also increased and the placebo effect has increased over time. Also, Dr Kirman says the immune system is strongly affected by stress. “If you are taking something that makes you feel better, or you feel like you’re doing something to help yourself, that can in a way boost your immune system, or keep your immune system in a healthy balanced state.”
Why do pharmacies sell these products?
Herbal supplements are sold alongside pharmaceutical medicine at pharmacies. There's a consumer demand. Pharmacists don’t make much money at all selling medicines, Kirman says. They make their money through selling all of these extra things. “In a way it’s sold as a health supplement, but there is very little evidence that it is contributing to your health in a positive way. When something is effective against a particular illness, at preventing it or treating it, it will be called a medicine and it will have to achieve the same stringent standards as a medicine.”
The manufacturers of health supplement products are probably convinced that their products work, although none responded to my emails asking for studies backing up their product claims. Dr Kirman says, “There’s a lot of misinformation. Once someone gets an idea in their head, it’s really hard to convince them otherwise. They say, “my product is safe, it’s got no side effects,” well, that’s because no one’s studying it. No one’s done a randomised controlled study looking at its effect on people.” They are relying on their customers coming back and saying this did something-or-other. “That’s not how medicines work.”