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Itchy Six Worst Supplements for Eczema

by Nutritionist Karen Fischer

Have you tried everything to treat your eczema while spending hundreds (or thousands) of dollars on products that just don’t work?


Well, you are not alone.


Now dietary supplements are the latest hack for eczema. But there is a lot of false hype and misinformation online and I am dismayed at the lack of knowledge on this important topic. 


Through experience, I've learned that most dietary supplements can be ineffective or even harmful for eczema, especially if taken in the wrong doses, while other supplements are truly great.


I'm a passionate advocate for safe supplementing to create healthy skin and I want to share this knowledge, so you can make informed choices. 


In this report, you’ll learn:


  • The itchy six worst supplements for eczema  

  • Safe and effective alternatives (e.g. from foods or optimal doses)

  • Plus you receive a bonus Supplement Guide with the optimal doses for radiant skin, so you can shop for supplements with confidence. 

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1. Green powder supplements
Chlorella, wheatgrass and spirulina - are they no good for eczema?

Why Wheatgrass, Broccoli, Spinach, Spirulina, Matcha, Green Tea and Chlorella Powder Supplements Could Make Your Skin Itchy.


If you have eczema, you know it's a condition that requires gentle care. While green powder supplements might seem like a healthy addition to your diet, they could actually make your eczema worse. Here's six good reasons why you should avoid green powders:


# 1. High Salicylate Content

Green powders are loaded with salicylates, natural chemicals with preservative actions that can worsen eczema in up to 52% of people with eczema (Loblay, 1986). 


# 2. Amines from Green Extracts

Spinach and broccoli powders contain amines, which can worsen eczema symptoms in up to 36% of people with eczema (Loblay, 1986; Worm, 2009). 


# 3. Heavy Metal Contamination

Green powder supplements, especially ocean/river derived ingredients can contain heavy metals. For example, nickel, a common skin irritant that can trigger dermatitis and eczema (Ahlström, 2019; Josefson, 2009) is found in high levels in spirulina (Al-Dhabi, 2013). Spirulina also contains mercury (Al-Dhabi, 2013).


# 4. Toxins in Spirulina

Spirulina produces toxins including βMAA, which can cause adverse effects such as liver damage, gout, stomach aches and skin reactions (Ravi, 2010; Gogna, 2023), which is the last thing someone with eczema needs.


# 5. Risks with Green Tea Extracts

Green tea extracts, including matcha, can cause contact eczema (Paulsen, 2022) and liver damage (Schönthal, 2011). Black Tea is also high in salicylates (Malakar, 2017), which can exacerbate eczema (Loblay, 1986). 

# 6. Common Side Effects

Skin rash and skin irritation are common side effects of consuming spirulina and chlorella (Rzymski, 2017), two common components of green powder supplements. This is especially concerning for those already dealing with eczema.



If you don't have eczema, green powder supplements might be fine for you. However, if you have eczema, are pregnant or breastfeeding, or a child, they carry risks due to their salicylate and amine content, heavy metal contamination and potential for skin irritation. 

2. Vitamin A supplements
Vitamin A and cod liver oil supplements

Why Vitamin A Supplements Aren't Ideal for Eczema (And a Better Alternative).


Retinol forms of vitamin A can work wonders for acne by reducing skin oiliness (Zasada, 2019), but if you have eczema, it's best to steer clear of vitamin A supplements. Here are four compelling reasons why vitamin A supplements are bad for eczema-prone skin, along with a safe and affordable alternative (hint: from food).


# 1. Vitamin A Dehydrates Skin

Fat soluble vitamin A (retinol) reduces sebum production in the skin, which is why it's effective for acne (Zasada, 2019). However, for eczema, this is bad news, as it can make skin feel tight, dry and prone to flaking. When dealing with eczema, you want to maintain skin hydration and oiliness to avoid exacerbating symptoms.


# 2. Immune System Imbalance

Eczema is often linked to an imbalance in the immune system, with a dominance of Th2 immune function (Brandt, 2011). High-dose vitamin A supplements can suppress Th1 and increase Th2 immune function, potentially worsening eczema (Schuster, 2008). Given this, avoiding vitamin A supplements is advisable for those with eczema.


# 3. Increased Risk of Allergies

A comprehensive meta-analysis of seven studies found that vitamin A supplement-ation was associated with an increased risk of developing allergic diseases, including eczema (Su, 2022). This increased risk suggests that people with eczema should be cautious with vitamin A supplements.


# 4. Cancer Risk

Artificial beta-carotene, which is commonly found in multi-vitamin supplements, may increase the risk of lung cancer (Kordiak, 2022). A systematic review also showed that long-term use of supplements containing beta-carotene, vitamin A or vitamin E was associated with higher mortality rates (Bjelakovic, 2007). Therefore, you are better off obtaining vitamin A through food, e.g. simply eat half a small carrot each day. 



Ensure the multi-vitamin supplement or beauty supplement you purchase does not contain vitamin A, retinol or beta-carotene. If you are pregnant or breastfeeding, avoid vitamin A supplements, cod liver oil, and liver as high dose vitamin A can affect your unborn baby. 

Still, we all need vitamin A for skin health, so a better alternative is vitamin A rich food such as carrot (¼ cup daily), pumpkin, lettuce and fresh fish to get your vitamin A fix. 

3. Collagen 
Collagen supplements - are they good for eczema?

Why Collagen Supplements Don’t Live Up to Their Grand Claims. 

Collagen supplements have gained popularity for their purported benefits for wrinkles, hair and joints. But is there any evidence collagen can help eczema and could they make you itchier? Here are six reasons why collagen supplements might be a waste of money:


# 1. Not Cruelty-Free and Contains GMOs

Collagen supplements are mostly made from the leftover bones, skin, joints and muscles of pigs (porcine), cows (bovine) and fish (marine) (Dewi, 2023), making them not cruelty-free or halal, and a bit gross. Vegan collagen is genetically modifying bacteria and yeast (Wang, 2017) and the effects of GMOs on our health are unknown. Most brands hide the collagen source making it hard for us to make an informed decision.


# 2. Collagen is Not Absorbed Properly

According to Harvard Health, no human studies have definitively shown that orally consumed collagen can increase the collagen levels in the skin, hair or nails (Patel, 2023). This is because our bodies can't absorb collagen in its whole form. There are 28 types of collagen and the skin needs type IV collagen (Abreu-Velez, 2012) which is not usually supplied in collagen supplements. 


# 3. Collagen Does Not Improve Skin Health

A study comparing people taking a bovine collagen supplement (type I collagen) or placebo found that consuming collagen supplements for 1 year does not improve skin health (Nat Clin Prac Rheu, 2008). 


# 4. Contamination Risk

Collagen supplements can contain endotoxins, that can cause adverse immune responses when it enters your bloodstream (Alves, 2022). 


# 5. Contains Histamine and Sulfites

Sulfites and histamine are compounds known to exacerbate eczema symptoms like itching. Studies have shown that more than 30% of people with eczema are sensitive to histamine (Loblay, 1986; Worm, 2009), indicating that collagen supplements could cause itching.


# 6. Allergic Reactions/Anaphylaxis Risk

Fish collagen supplements are associated with anaphylaxis attacks in people with eczema (Fujimoto, 2016; Kalic, 2020). 



Despite the popularity of collagen supplements, there's no scientific evidence to suggest that they offer any benefit for people with eczema. Eczema is not caused by collagen deficiency, and our bodies make collagen when we eat a healthy diet rich in protein, zinc, silica, copper and vitamin C. Save your money and see page 13 for a superior alternative. 

4. High Dose B Vitamins
Are B vitamins good for eczema?

Why High Dose B Vitamins Aren’t Good for Eczema. 

When it comes to eczema management, taking a multi-vitamin supplement poses hidden risks that could make your eczema worse. Let's delve into why excessive intake of B vitamins is a health no-no that is bad for pretty much everyone:


# 1. Nerve Damage (Neuropathy)

While vitamin B6 is essential for skin health, excessive B6 intake causes nerve damage resulting in skin tingling, numbness, burning and dermatitis (skin rashes) (Hadtstein, 2021; Muhamad, 2023). Vitamin B6 deficiency can also lead to skin rashes so you need some vitamin B6 in your diet. The Therapeutic Goods Administration (TGA) in Australia states: “products containing daily doses over 10 mg of vitamin B6 must carry a warning about peripheral neuropathy.” However, many supplement brands contain excessive amounts of B6, which is a concern. They have no idea their high dose B6 causes nerve damage and skin rashes. Buyer beware! 


# 2. Red Skin Flushing and Itching

Vitamin B3 is essential for skin health. However, the Niacin form, which is commonly found in supplements, can cause a release of inflammatory substances that cause a skin flushing reaction, involving redness, burning, tingling, skin irritation and itching of the skin (Papaliodis, 2008). Eczema is already a painful condition and this B vitamin could make eczema worse. Stick to the DV or  Recommended Daily Intake which is between 14-16 mg for adults and choose Nicotinamide instead as it does not cause itching. 


# 3. Deficiencies

While B-group vitamins are essential nutrients, the key lies in maintaining balance. Excessive intake of any single B vitamin, especially in high doses, may disrupt this balance and may mask deficiencies in other B vitamins (Mills, 2018). For eczema sufferers, this imbalance may manifest as eczema flares. So avoid taking single B vitamins and take all of the B vitamins in a multi-vitamin formula (but check the doses!). 



While B-group vitamins are vital for skin health, the idea of high-dose supplementation can be hazardous. Boycott multi-vitamin supplements that contain high levels of B vitamins (e.g more than 10 mg of B6 or 20 mg of B3) as they may be unsafe. Moderation is the key when it comes to supplementation. See page 19 for B3 dose information.  

5. Probiotics
Probiotics for eczema - do they work?

Why Probiotics Have Fallen From Grace as a Treatment for Eczema. 


Adding healthy bacteria to the body seems like a logical approach because eczema patients often show an imbalance of bacteria on their skin. However, over time, the initial excitement around probiotics for eczema has waned. In reality, the results have been underwhelming. Let’s look at the science around probiotics to see why: 


# 1. Probiotics Don’t Help Eczema

While giving probiotics to pregnant mothers or infants under the age of one may help to reduce some cases of eczema, probiotics have limited, if any, effects on eczema in children and adults, according to the National Eczema Association, and research by Jiang, 2020 and Tan-Lim, 2021. Scientists from one study stated “the long-term effects of probiotics on eczema are questionable” (Jiang, 2020). 


A Cochrane review of 39 randomised controlled trials found current probiotic strains don't improve eczema symptoms, as rated by patients. Probiotics also have little to no effect on the quality of life of people with eczema. Therefore, using probiotics to treat eczema is not currently supported by evidence (Makrgeorgou, 2018).


# 2. SIBO Risk and Side-Effects

A study showed that people who had recently taken probiotics were more likely to test positive for a type of Small Intestinal Bacteria Overgrowth (SIBO) that's associated with high methane levels, which can lead to constipation (Achufusi, 2020). Another study found when participants stopped taking probiotics, their brain fog and gastro-intestinal symptoms improved (Rao, 2018). Metabolic acidosis (too much acid in the body), which can worsen eczema, was another side-effect seen in people taking probiotics (Rao, 2018). 


# 3. New Diet to Upgrade Your Microbiome

The best way to improve your gut bacteria is to change your diet. Studies show how modifying your diet can rapidly change the diversity of your microbiome bacteria within a few days (David, 2014; Han, 2020). 



After taking antibiotics, a short course of probiotics may help repopulate the gut. However, probiotics are unlikely to significantly help your eczema. Avoid long-term use of probiotics and eat a healthy, fibre-rich diet as it’s the best way to encourage microbiome diversity and gastrointestinal health. No pill can fix a bad diet!

6. High Dose Vitamin C
Eczema Diet Worst Supplements 6_edited.j

Why Mega-Dosing with Vitamin C is Not Good for Eczema. 


Vitamin C is often touted in blogs as one of the best supplements for eczema, yet I could not find a single study that backed up this claim. One study found people with eczema had lower blood levels of vitamin C (Shin, 2016), but this correlation is not reliable evidence. Vitamin C is essential for health: If you have scurvy, just 10 mg of vitamin C will reverse this disease (Alpers, 2008). So why do people recommend mega-doses when 10 mg saves our skin? Here are three reasons why less is more when it comes to vitamin C: 

1. Adverse Reactions are Common

The FDA gets thousands of complaints annually about negative reactions from supplements, with vitamin C being the second most frequently reported source of adverse effects, following vitamin E. (Timbo, 2018). Diarrhoea is a common side-effect (Sestili, 2018) and this could damage your microbiome. More concerning, high dose vitamin C can cause oxalate crystallization, and formation of advanced glycation end products (Wróblewski, 2005), which can damage your kidneys and your skin. 


# 2. Prooxidant Effect

While vitamin C in low dose has an anti-inflammatory effect, when high doses are consumed, it has has the opposite effect, becoming prooxidant  (Wróblewski, 2005). Prooxidants can harm DNA, disrupt cell membranes and interfere with the body's repair mechanisms (Sotler, 2019). If you have eczema, this is precisely the kind of damage you want to avoid.


# 3. Mega-Dosing Affects Other Nutrients

Consuming high doses of vitamin C daily may hinder the absorption of iron, copper and vitamin B12 (Kaźmierczak-Barańska, 2020). So it's best to avoid high dose vitamin C because it’s risky and unnecessary. You get the most benefits when you take small doses. 



Although vitamin C does not cure eczema, it contributes to overall skin health. If you choose to take vitamin C supplements, the United States DV for vitamin C is 90 mg for adults and children age 4 years and older. The Australian RDI is lower, at 45 mg per day for adults and between 35 mg and 40 mg for children. You can also support your vitamin C intake by eating a healthy diet rich in vegetables and fruit.

Supplement guide for eczema
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Optimal Supplement Dosages for Radiant, Smooth Skin


This is what to take (and how much) for clear skin. If you are pregnant or breastfeeding refer to your health practitioner for doses. Combine this information with a healthy eczema diet for holistic eczema care. 

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Which Types of B Vitamins are Best?


Not all supplements are created equal. Some B vitamins can be purchased in methylated (biologically activated) form so your body can easily use them.


Unfortunately, most B vitamin supplements are the regular kind, where your body must convent them through a complicated enzyme process, before your body can use them to create energy and healthy skin. If your enzymes are not working properly, or if your gut microbiome is compromised, you won’t be getting a steady supply of activated B vitamins. So the B vitamins you buy can be useless if your body does not convert B vitamins effectively.


Look for: Pyridoxal-5-phosphate is the active form of vitamin B6, Mecobalamin is the active form of Vitamin B12, and Levomefolic acid is an active form of folate. 


mg = milligrams



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eczema reports

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Supplement Reference:

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Karen, nutritionist and author

Karen Fischer has a Bachelor of Health Science Degree from the University of New England in Armidale and she has been a qualified nutritionist for 20 years, currently registered with IICT. She previously ran the Eczema Life Clinic in Sydney and is the author of 7 health books.  Karen shares her family favourite Eczema Diet recipes, her latest tips via podcasts and answers your burning questions each week. Karen also shoots most of  the photos for our website. And Karen's daughter Ayva draws the graphics. 

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Bonnie, nutritionist

Bonnie grew up suffering from eczema and in her teen years she found success on Karen's eczema diet program which inspired her to complete a Bachelor of Health Science, majoring in Nutrition and Health Promotion and she is registered with NSA. Bonnie manages the Eczema Diet Support Membership. 



Katie specialises in gut health and she creates many of the recipes. published on this site. Katie has worked with Karen Fischer for many years and she helps people to successfully follow the various Eczema Diet programs including the FID Program. Katie is a registered nutritionist with ATMS.  

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