Is Your New Diet Making Your Psoriasis Worse?
No sugar. Low carb. All the fat! Whether these eating edicts work on whittling your waist or not, there's evidence that certain diets can start (or stop) a psoriasis flare.
There’s a reason why dermatologists ask you about your diet when examining your skin—the severity of your psoriasis can often be directly linked to what you’re eating.
That’s because certain foods can fan the flames of inflammation, a usually natural, normal part of being a human that protects us from infections and helps us heal after accident, injury or illness, explains Suzanne Dixon, R.D., an epidemiologist with Cambia Health Solutions in Portland, Oregon. While short-term, acute inflammation is harmless, long-term inflammation is a breeding ground for myriad chronic conditions, psoriasis included. And the more sugar-fat-and-alcohol-laden your diet, the more fiery your inflammatory response may be.
That type of diet can also trigger something of a vicious cycle, too: A recent systematic review published in JAMA Dermatology analyzed the relationship between diet and psoriasis and made some recommendations: The strongest favored low-calorie diets for people with psoriasis who are also obese and overweight.
“There is a link between excess weight and symptom severity in those with psoriasis, and this is thought to be due in part to the fat cells contributing to increased inflammation,” explains Marisa Garshick, M.D., a dermatologist at Medical Dermatology & Cosmetic Surgery (MDCS) in New York City. “The review thus suggests that psoriasis patients who follow a hypocaloric diet to lose weight can help improve symptoms of psoriasis.”
Additionally, several studies, including one published in Expert Opinion on Biological Therapy, have shown that when comparing psoriasis patients on a low-calorie diet to those on a normal diet, those on a low-calorie diet lost more weight and had a greater reduction in psoriasis severity.
The Skinny on Diets and Psoriasis
When it comes to diet and skin health, including how symptoms respond to nutrition tweaks, there will always be differences person to person. That's why Dixon encourages her clients with psoriasis (or any other autoimmune disease) to be open to experimenting with different dietary patterns. “What works for one person may not work for you,” she says. “Don't get discouraged, just know that your unique physiology and immune function may need a different approach.” What that means is that you could cut out dairy and notice an improvement, while your friend who also has psoriasis notices no difference.
Wondering how today’s most popular diets fair for those suffering from inflammatory conditions such as psoriasis? Here’s what the experts have to say—and how they rate each one in terms of its effectiveness in mitigating flare-ups.
DASH Diet: A
The DASH diet, or Dietary Approaches to Stop Hypertension, was first developed for patients at-risk for cardiac conditions. But now it's being hailed as a diet that's healthy for everyone, particularly because it focuses on reducing sodium, which can increase blood pressure. The premise is pretty simple: You swap processed foods for fresh and frozen fruits and veggies, especially those high in potassium, calcium and magnesium, which have been shown to lower blood pressure, explains Roger E. Adams, Ph.D., a personal trainer and owner of eatrightfitness in Houston, Texas.
That's good news for people with psoriasis because high blood pressure can increase blood flow to the skin, causing red splotches and possibly itchiness, Dr. Adams notes. The diet also limits foods high in saturated fat, highly refined carbs, and alcohol. “These tactics will naturally lead to less of an inflammatory response in the body, which will help the skin and reduce flare-ups,” he adds.
This low-carb eating model originated as a therapeutic treatment for children who suffer from epilepsy. The goal when following the Keto diet is to keep your daily carbohydrate intake under 30 grams, which is quite a difficult feat for most people. To make this more tolerable, you eat a lot of healthy fats and a moderate amount of protein. The combination transitions your body into a state known as ketosis, or when the body burns fat for energy instead of sugar.
The ketogenic diet has some high notes: “It does lower insulin and glucose (blood sugar) levels in the body, which can have very positive effects on psoriasis symptoms," says Dixon. (Psoriasis itself has been linked to an increased diabetes risk.) "Plus, it's very high in fat, and for some people that can translate into softer, more supple skin,” she says. “The diet also cuts out nearly all carbohydrates, including simple sugars, which can reduce inflammation and improve symptoms.” The diet can also help mitigate inflammation by promoting rapid weight loss, which research has linked to a decreased incidence and severity of psoriasis.
The downsides? It can be hard to stick to nearly no carbs for the long haul, and the jury is still out on whether you should even try.
Intermittent Fasting: B
This increasingly popular dietary trend, known as “IF,” involves eating in patterns, or cycles of time, and intertwining those with periods of fasting. “There are many ways to practice IF, such as alternate-day fasting (eating nothing or a low-calorie meal on fasting days, then eating normally every other day), one meal a day, eating five days per week and fasting two, and more,” explains Naomi Whittel, author of Glow15: A Science-Based Plan to Lose Weight, Revitalize Your Skin, and Invigorate Your Life. “Many studies have shown an impressive list of health benefits from IF, such as increased insulin sensitivity, lowered inflammation, boosted autophagy (cellular clean-up), decreased risk of chronic diseases like diabetes and heart disease, more self-control around eating, and improved body image and self-esteem due to fat loss.”
Specifically, for psoriasis and other autoimmune conditions, IF can be particularly beneficial, because it gives your body a break from digesting food, which means it can spend less time in inflammatory mode and more time in repair mode. In fact, one study published in Cell Reports found that diets incorporating fasting had a positive effect on reducing autoimmunity.
To be sure you are fasting safely, Whittel says it’s important to have proper hormonal balance and not be in a high state of chronic stress. “While the science is strong that IF is an important tool to harness if you’re suffering from chronic symptoms, there are a vast amount of different ways to modify it to meet you where you are today,” Whittel adds. If you’re unsure of what level of IF would serve you best, she recommends working with a nutritionist for some initial guidance.
Also known as the Paleolithic or caveman diet, Paleo is like Keto in that it tends to consist of higher fats and lower carbs than the Standard American Diet (SAD). The main objective when following the Paleo diet is to consume whole, non-processed food. It strives to eliminate gluten and all grains, legumes, dairy, and sugar.
“Since paleo is low in simple sugars and white flours, both ingredients in many processed foods and likely contributors to inflammation in the gut, reducing or eliminating these foods will likely help improve gut health,” explains Dr. Adams. “If the lining of the small intestine gets inflamed from a diet high in processed foods and simple sugars, then malabsorption issues or inflammation may occur.” At the very least, a paleo diet can help people with gut-related issues lower their inflammation while they determine which foods are exacerbating their issues.
It’s worth noting, however, that Paleo limits some nuts and all legumes and grains, which are good sources of healthy fat and fiber. “Dietary fiber supports a healthy microbiome, and this, in turn, appears to be connected to many chronic conditions, including psoriasis,” says Dixon. The other downside of paleo is the reliance on red meat. “There is increasing evidence that a couple of substances in red meat—Neu5Gc and galactose-alpha-1,3 -galactose—can have proinflammatory effects,” she adds.
The Whole30 is less of a diet and more of a dietary challenge to find out what your body’s sensitivities may be. It’s typically done for 30 days and involves eliminating sugar, alcohol, grains, legumes, soy, and dairy, and then slowly reintroducing them back into your diet to see how the body reacts. “This diet is still very new with no studies to show the effects on the skin, however, with the elimination of refined foods and alcohol consumption this diet should definitely show improvement,” says Michele Green, M.D., a dermatologist affiliated with Lenox Hill Hospital and Mount Sinai Queens in New York City.
Atkins is also a low-carb diet, which is why it’s equally as helpful for psoriasis patients as the keto diet is. Both encourage high fat and low carbs; however, the key difference is that the Atkins diet allows for slightly more calories from protein (30%) than keto (20%). Just as with keto, benefits include lower insulin and glucose levels and possibly, weight loss. A downside of the Atkins diet is that it suggests avoiding higher carb veggies and fruit like spinach, carrots, and grapes all of which are proven to dampen inflammation.
“One recent paper published in Free Radical Research noted that eating a diet rich in antioxidants may help reduce the damage of oxidative stress caused by psoriasis, especially within the skin itself.” This is one of the main reasons why Dixon discourages low carbohydrate diets for those suffering from psoriasis and other autoimmune diseases. “Cutting out added sugars and ultra-processed foods is absolutely a great idea but cutting out higher carb vegetables and most fruit isn’t going to improve inflammatory conditions,” she adds.
Detox Diets: F
Detox diet is an umbrella term for myriad plans that involve eliminating toxins from one’s body. These tend to be like intermittent fasting in the sense that detox diets involve periods of not eating or eating a restrictive diet of only fruits, vegetables, and water. Most skin and nutrition experts don’t recommend these types of diets, as there is not enough evidence to support their ability to improve skin or bodily health in any way. And, while they may encourage weight loss, it tends to creep back on (and sometimes even with a little extra) once the diet is no longer being followed.
“Psoriasis is a long-term, chronic health condition, so even if a detox diet temporarily improved symptoms, it's not addressing the underlying factors that may be contributing to flare ups. In this sense, it isn't going to meaningfully improve outcomes for someone who wants better control over skin health,” says Dixon.
- Diet and psoriasis study review: AMA Dermatology. (2018). “Dietary Recommendations for Adults with Psoriasis or Psoriatic Arthritis.”
- Dietary fiber study: Clinical Experimental Gastroenterology. (2019). “Inflammation in gastrointestinal disorders: prevalent socioeconomic factors.” ncbi.nlm.nih.gov/pubmed/31410046
- Eating an antioxidant-rich diet: Free Radical Research. (2019). “Oxidative stress involvement in psoriasis: a systematic review.” ncbi.nlm.nih.gov/pubmed/31392915
- Link between weight loss and psoriasis treatment: Expert Opinion on Biological Therapy. (2014). “The effect of weight reduction on treatment outcomes in obese patients with psoriasis on biologic therapy.” ncbi.nlm.nih.gov/pubmed/24661040
- Study about fasting and autoimmunity: Cell Reports. (2016). “Diet mimicking fasting promotes regeneration and reduces autoimmunity.” ncbi.nlm.nih.gov/pmc/articles/PMC4899145/