Think you can’t overdose on face cream? Or the more vitamins and minerals you take, the better?
Think again. As our beauty routines become more complicated, we must be wary of accidental overdosing of ingredients or mixing and matching products with potentially dangerous results.
“We’re overloading ourselves with too many topical products and crazy amounts of supplements,” says aesthetic expert Dr. Mervyn Patterson of Woodford Medical.
He warns that this can cause skin damage, interfere with medical tests and potentially lead to serious health problems.
Read on for more information…
Be aware of biotin
Biotin, or B7, is a very popular vitamin commonly used in hair, skin and nail supplements. It is water soluble, which means it does not build up in the body and you do not need large amounts. ‘Biotin is only useful as a supplement if you are deficient,’ says nutritionist Emma Bardwell, who warns that excessive use can carry dangers, including interfering with both thyroid and heart tests.
Last year, the British Generic Manufacturers Association wrote to healthcare professionals warning that biotin can affect thyroid function results, and that patients should be asked about the use of biotin or skin, nail and hair supplements before testing.
Shockingly, biotin can also interfere with heart test results. In 2019, the FDA recalled that high doses of biotin can significantly interfere with tests used to measure troponin, a protein in the heart muscle that is released into the bloodstream during a heart attack, raising concerns about both falsely high and low results depending on the test.
‘If you go to hospital with chest pain, your troponin levels will be measured,’ says Dr Oliver Guttmann, consultant cardiologist at Wellington Hospital, part of HCA Healthcare UK. ‘To monitor these levels, biotin can be used, so a biotin supplement may affect the reading. The concern is about falsely low/negative troponin levels because heart attacks can be missed.”
Similarly, biotin is used to monitor the thyroid gland, which can cause incorrect readings. Dr. Guttman says false high and low readings were detected depending on which tests were used.
The NHS says less than 0.9mg per day is unlikely to cause harm. But in the wild west of the supplement world, it’s easy to buy tablets containing as much as 12 mg. Although the packaging recommends consulting a doctor or pharmacist if you are taking medications or have a medical condition, we are conditioned to consider supplements safe. How many people actually do that? Make sure you follow their advice.
Keep an eye on vitamin A
Hailed as a skincare wonder ingredient, retinol increases collagen production. But in April, the EU warned about overexposure and is implementing new legislation to limit retinol content in products.
Experts warn that overuse of retinol (applied as creams and serums) can irritate and thin the skin
“The contribution of vitamin A from cosmetic products to overall consumer exposure, although low, may be of concern for consumers with the highest exposure to vitamin A (5 percent of the total population) from food and dietary supplements,” the Scientific Institute said. Consumer Safety Committee.
‘If you have too high a concentration in your system, it can damage the liver and cause bone thinning. I wouldn’t worry about skin irritation as much as the systemic effect,” says Dr. Patterson, although he cautions that overuse of retinol can only irritate and thin the skin.
The UK RDA for women is 600 mcg (700 mcg for men), while the NHS website advises not to exceed 1,500 mcg through food and supplements. The Mayo Clinic warns that more than 3,000 mcg per day in the long term can cause the problems already mentioned, as well as joint and bone pain, headaches, nausea and diarrhea.
Vitamin A is often marketed as a beauty supplement that can be purchased cheaply and easily in very high doses. In fact, it’s feasible to take one along with a general multivitamin (which provides more than 100 percent of your daily needs), eat a serving of spinach and carrots, and then use a topical cream containing retinol — all in all. together almost 10,000 mcg.
…and too much vitamin C
‘The RDA for adults is 40 mg per day, but this is the lowest level to prevent things like scurvy,’ says Bardwell. ‘There is a trend to take very high doses of vitamin C for skin health and immunity. The upper limit is 2,000 mg per day and even 1,000 mg can cause stomach problems: nausea, vomiting and gastrointestinal complaints.’
It is easy to consume these levels, especially in powder form. ‘High doses are unlikely to cause harm, but it can certainly cause discomfort if taken orally, and is likely to be very expensive as an infusion.’
Don’t mix and match
If you’re a fan of the TikTok trend for layering skincare products, beware, as cross-mixing ingredients can be harmful.
“The skin can only absorb a limited amount and mixing products can be problematic,” says Dr. Patterson. Retinol (or other forms of vitamin A) and vitamin C cream applied at the same time can cause irritation, as can vitamin C and AHAs, or retinol and salicylic acid, which can dry out the skin.
Dr. Patterson advises against using two products with the same active ingredients and ‘stick to five basic products from the same range’.
There’s something strange…
Ideally, we should get our omega-3 through fatty fish, for example. In addition, supplements, which are said to help combat dry and irritated skin and promote hair and nail health, should be used with caution by people taking blood thinners, due to fears of an increased risk of bleeding.
Omega-3 supplements should be used with caution by people taking blood thinners
‘Too high a dose of omega-3 can change the way the body uses it, making warfarin possible [blood thinner] more powerful,” says Dr. Guttman.
The British Heart Foundation recommends that if you take omega-3 supplements, you should aim for around 450 mg per day (and choose supplements that contain DHA and EPA omega-3). Fish oil is known to thin blood; a study of 56 healthy adults who took 640 mg per day for a month had reduced clotting.
Dr. Guttman says, “People respond differently, but stay within recommended limits and talk to your doctor about supplements.”
Other lesser known side effects of very high doses of fish oil may include heartburn and diarrhea.