Vitamin supplements have been found to be incredibly effective.
The industry’s market size is estimated at £40bn in 2022 and is expected to double by 2032.
Part of the appeal lies in the simplicity of the sale. Vitamins are essential because modern life is busy.
Therefore, taking supplements daily is an elegant solution.
However, health experts generally agree that vitamin supplements are poor substitutes for a healthy balanced diet and that vitamin supplements should only address specific deficiencies or needs. .
Additionally, there’s a “fine balance” between enough and too much that needs to be respected, explains scientist and supplement formulator Miles Taylor.
The industry market size is estimated to reach around £40bn in 2022
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She warns that exceeding recommended dietary allowances can upset this delicate balance and lead to overconsumption.
The specific effects of taking too many vitamins depend on the supplement and the amount taken.
A useful starting point is to distinguish between fat-soluble and water-soluble vitamins.
“Overconsumption of fat-soluble vitamins can result from acute toxic overdosage (one large intake exceeds the daily recommended intake) or chronic toxic overdosage due to ingestion of large amounts of vitamins over a long period of time. It could be,” Amy Reichelt explained. , Chief Innovation Officer, PurMinds Neuropharma
She told GB News: “Similar overdosage effects are seen with water-soluble vitamins, but the kidneys are able to filter out more of the active chemicals in the urine than they store in fatty tissue.”
What counts as a fat-soluble vitamin and what are the risks?
vitamin A
Vitamin A is a fat-soluble vitamin best known for maintaining eye health.
It is available in two forms: an active form of vitamin A (retinoid) and a provitamin commonly found in animal products.
A (carotenoids found in colorful fruits and vegetables). Our liver stores vitamin A, which helps prevent hypervitaminosis A (abnormally high levels of the vitamin).
Research shows that too much vitamin A can cause acute and chronic adverse effects such as headaches, muscle and joint pain, liver dysfunction, poor bone health, and skin changes.
Acute toxicity from vitamin A (called hypervitaminosis A) has been reported in Arctic explorers who ingested large amounts of animal liver, and can cause rash, abdominal pain, vomiting, and increased intracranial pressure. These cases are extremely rare.
Additionally, vitamin A is also known to be teratogenic (causing fetal malformations), so women planning pregnancy should avoid using treatments containing retinoids, such as tretinoin.
What is a safe amount to consume?
Some research suggests that consuming more than an average of 1.5 mg (1,500 μg) of vitamin A per day for many years can have an effect on your bones, making you more likely to break bones as you get older.
If you take supplements containing vitamin A, the NHS advises that your daily intake from food or supplements should not exceed 1.5mg (1,500μg).
vitamin D
Vitamin D is another fat-soluble vitamin that can fall into the danger zone.
The “sunshine vitamin” is a major regulator of calcium balance and is essential for healthy bone development.
Many people rely on vitamin D supplementation to meet their needs during the winter, but Taylor warns that this can lead to “chronic overdosage”.
Symptoms include fatigue, nausea, diarrhea, and hypercalcemia (when blood levels of calcium are too high).
Research shows this can lead to weakened bones, kidney stones, and heart and brain dysfunction.
Another study shows that taking more than 10,000 IU (about 250 micrograms) of vitamin D per day can cause hypercalcemia, which can lead to kidney stones and abdominal pain.
The paper suggests that this, combined with the intake of abnormally high doses of calcium, may increase the risk of developing colon polyps (growths on the lining of the colon that can become cancerous) and causing stroke. It has been found.
In extreme cases, research suggests that vitamin D toxicity can cause kidney failure, calcification of soft tissues throughout the body (including coronary blood vessels and heart valves), arrhythmias, and even death.
How much is safe to take?
When taking vitamin D supplements, the NHS says 10 micrograms a day is enough for most people.
Do not take more than 100 micrograms (4,000 IU) of vitamin D per day as it may be harmful.
This applies to pregnant and breastfeeding women, adults, including the elderly, and children aged 11 to 17.
In extreme cases, vitamin D toxicity can lead to kidney failure and soft tissue calcification throughout the body.
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vitamin E
Vitamin E helps maintain healthy skin and eyes and strengthens the body’s natural defenses (immune system) against disease and infection.
However, it can be harmful if taken in excess.
Excessive intake of vitamin E has been shown to thin the blood and cause fatal bleeding.
Similarly, it can interfere with blood clotting, the body’s natural defense against excessive bleeding after an injury.
Furthermore, vitamin E supplementation has also been linked to cancer. One study demonstrated that vitamin E intake may potentially increase the risk of prostate cancer in some men.
How much is safe to take?
According to the Department of Health and Social Care (DHSC), taking less than 540 mg (800 IU) of vitamin E supplements a day is unlikely to cause harm.
vitamin K
Vitamin K is a group of vitamins that the body needs for blood clotting and aids in wound healing.
There are two types of vitamin K1, which is found in green leafy plants, and vitamin K2, which is found in fermented foods such as natto and cheese.
Vitamin K toxicity is not a major concern for the average person who follows a balanced diet or takes standard supplements.
“This is primarily due to the rapid use of vitamin K in the body and short half-life,” Taylor explained.
However, this does not exclude the possibility of toxicity, especially under certain conditions.
For people taking anticoagulants (blood thinners) such as warfarin, taking too much vitamin K can negate the drug’s effects and lead to an increased risk of blood clots, says the Office of Dietary Supplements (ODS). is warning.
Research suggests that patients taking these drugs should maintain consistent vitamin K intake to avoid fluctuations in the drug’s effectiveness.
How much is safe to take? According to the DHSC, taking vitamin K supplements of less than 1mg per day is unlikely to cause harm.
Too much vitamin K can interfere with the action of anticoagulants (blood thinners) such as warfarin
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What about water-soluble ones?
vitamin B6
Vitamin B6 (pyridoxine), also known as pyridoxine, is a water-soluble vitamin that plays an important role in a wide range of physiological functions, including storing energy from proteins.
Despite its importance, there is a threshold for the amount of vitamin B6 that the body can tolerate before side effects begin.
Beyond this threshold, studies have shown that a toxicity known as pyridoxine-induced neuropathy can occur, leading to damage to sensory neurons and causing numbness, pain, burning and difficulty walking in the limbs. Shown.
According to Teller, the supplement formulator, vitamin B6 toxicity is typically caused by taking long-term supplements at high doses well above the recommended daily intake, and that food alone can cause such effects. It is said that reaching such high levels is rare.
How much is safe to take?
The DHSC advises not to take more than 10mg of vitamin B6 per day in supplements unless directed by your doctor.
vitamin C
Vitamin C, also known as ascorbic acid, has several important functions.
These include:
- Helps protect cells and maintain health
- Maintaining healthy skin, blood vessels, bones, and cartilage
- aid in wound healing
Unlike fat-soluble vitamins, excess vitamin C is generally excreted in the urine, so it is relatively difficult to overdose.
However, when taken in very high doses, it can cause adverse health effects.
According to research, these negative health effects include gastrointestinal disturbances and kidney stone formation due to increased amounts of oxalate in the urine.
Excessive intake of vitamin C can cause gastrointestinal problems such as diarrhea and may impair the body’s ability to increase high-density lipoprotein (HDL) cholesterol in people taking combination drugs of niacin and simvastatin. The Office of Dietary Supplements (ODS) warns that
This drug combines the vitamin niacin and the statin simvastatin (Zocor) and is taken to treat high cholesterol.
How much is safe to take?
According to the DHSC, taking less than 1,000mg of vitamin C supplements per day is unlikely to cause harm.
Excessive intake of vitamin C can also cause gastrointestinal disorders
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Are there any benefits to taking vitamin supplements?
There is limited evidence that daily intake of essential vitamins and minerals actually has the desired effects.
Most studies have not found any benefit from multivitamins to protect the brain or heart.
But a standard once-daily multivitamin has potential benefits and no risks.
The Physician Health Survey II is the most rigorous survey. This is the first and only large-scale randomized test to test a commonly taken multivitamin, as most people take, including daily requirements for 31 vitamins and minerals essential to good health. It was a clinical trial.
Researchers investigated the effects of long-term multivitamin use on various aspects of health in healthy men and found that:
- Men were 8% less likely to be diagnosed with cancer. The protective effect was greatest among men with a history of cancer.
- Lower risk of developing cataracts
However, another study of 450,000 people found that multivitamins did not reduce the risk of heart disease or cancer.
Given the lack of rigorous research, most experts recommend getting your vitamins and minerals from natural sources as often as possible.
This includes following a healthy, balanced diet consisting of lots of fruits, vegetables, lean meats, and whole grains.
general advice
If you plan on taking supplements, there are some important safety protocols to follow.
“Always follow NHS guidelines or the advice of your medical professional,” advised Dr Eamonn Laird, Lecturer in Nutrition at ATU Sligo and Assistant Professor at Trinity College Dublin.
Always avoid purchasing supplements outside the UK, EU, or online. You never know how much is actually in a supplement. It is wise to be “wise” as it may contain less or much more than what is listed on the label. says the doctor.
Additionally, vitamins and supplements, especially unappetizing preparations like gummy vitamins, should be kept safely out of the reach of children, as treating them like candy can lead to overdose. is important, warns PurMinds Neuropharma’s Ms. Reichert.
