What is dairy actually doing to your skin?

Dairy gets some bad press in the skin department. From cow's milk proteins apparently aggravating eczema  to  studies suggesting that high dairy intake is associated with acne , some consider dairy to be public enemy number one for skin, and this can indeed be the case in terms of allergy to the protein casein in particular, which produces side effects such as eczema, hives and skin rashes according to the NHS. For the rest of us, however, what’s the deal on dairy and skin health?

Liz Earle, for one, can't get enough of the stuff. Or at least, fermented dairy in the form of kefir. She attributes her clear, practically line free skin to both drinking and topically applying kefir to her daily , from a bystanders points of view, I can't argue with the results (it GLOWS IRL). To be frank, I'm feeling quite confused here- should we be cutting back for the sake of our complexions, or is a milky tea really no big deal where calm skin is concerned? I gave consultant dermatologist at the Cadogan Clinic  Dr Anjali Mahto  a call to clear things up.

Is dairy really public enemy number one for our skin?

“The scientific link between dairy and skin health is relatively small. Some propose that dairy promotes insulin and IGF1 production as seen in carbohydrate-rich diets, or that it contains growth hormones which increase androgen levels that in turn cause oil glands to produce more sebum, both of which could hypothetically cause flare-ups for skin conditions.

There is emerging scientific evidence that dairy products and foods rich in carbohydrates with a high glycaemic index (GI)  may aggravate acne, however, there is not much evidence supporting these theories at the moment. The link between acne and dairy is much weaker than the link between acne and sugar and, if anything, some studies seem to suggest that low fat dairy is more of an issue than full fat dairy. If you don’t notice that your acne particularly flares up after consuming dairy products then I would not recommend excluding them from your diet.”

How can you tell if dairy is causing skin flare-ups?

“Allergies tend to present themselves on the skin as rashes, whereas an intolerance may have more of an effect on your digestive system. If you suspect that dairy is the cause of skin issues then attempt to cut it out and keep a food diary, making note of your skin condition following this. However, for most people the causes behind conditions such as acne are complex and so simply cutting out dairy or changing your diet may not be sufficient or significant enough to clear up your skin. Therefore, I would always advise visiting a dermatologist, who will be able to assess your skin thoroughly and advise on other possible causes.”

Does the type and quality of dairy we consume make a difference in terms of impact on skin?

“As above some studies have previously suggested that low fat dairy causes more problems for the skin than full fat dairy, however, the reasons for this are still unclear. There is also an interesting area of research that looks into the benefits of probiotics , which can be found in dairy products such as yoghurt and kefir . Probiotics may also have a role to play in chronic skin conditions—things like acne, rosacea, and eczema. Impaired digestion can release stress hormones such as cortisol, which can trigger an overproduction of sebum, leading to blocked pores  and spots. By reducing the gut stress associated with impaired digestion through oral probiotics we can in turn help to reduce inflammation associated with eczema, dermatitis  and acne. It’s important to note that much of this is still speculation, but it's an interesting area of research.”

So probiotic dairy could be good for skin, but otherwise what’s your stance on excluding the likes of low fat dairy?

“If you don’t notice that your skin flares up after having dairy products then I would not recommend excluding them from your diet. If you really want to maximise the potential of your diet for clearer skin, scientific data suggests that nutrients such as vitamin A, omega-3 fatty acids, zinc and niacinamide (vitamin B3)  may help some acne sufferers.”

Rosacea is another very common skin condition that flares up, and emerging data shows that those who suffer with rosacea affecting the eyes (ocular rosacea) especially benefit from supplementation with omega-3 fatty acids. Time and more research will tell if this can be extrapolated to rosacea affecting facial skin also, but it’s heartening.”

In terms of reasons to include dairy in your diet for the sake of your skin, lactobacillus, a type of bacteria usually found in yoghurt, has been shown to produce proteins which not only have antimicrobial activity against the bacteria that cause acne spots , but also have direct anti-inflammatory activity. However, any supplementation should be discussed with your doctor or dermatologist in accordance with any other topical, oral or antibiotic treatments that may have been prescribed.”

What’s the score on dairy alternatives? What would be your choices with skin health in mind?

“ Dairy alternatives  such as soy, almond  and coconut milk can sometimes be sweetened with sugar to make them taste more like cow’s milk - and there is evidence to suggest that these levels of sugar could cause skin problems too . Soya milk  can be high in added sugars and refined sugar may be implicated in skin ageing  and acne. Therefore, these alternatives should be consumed in moderation, and always check the packaging for added sugars before you buy.”

Vegan  or limiting dairy?  Read our rundown of 9 cow’s milk alternatives

Follow Dr Anjali on Twitter  @DrAnjaliMahto  and Anna  @AnnaMaryHunter