Psoriasis is a chronic inflammatory skin disease that can flare up due to stress, infection, dry skin, medications, and even some foods. While some think fasting may help psoriasis, there is no conclusive evidence supporting this claim.

Fasting is a popular method to help eliminate certain foods from the diet, boost metabolism, and speed weight loss. It requires going without food for specified periods.

Researchers have looked at using fasting to treat psoriasis. Currently, there is not enough evidence to recommend using fasting specifically for this condition.

Still, people with psoriasis may want to check with a doctor to see if they should try fasting. They should be aware, as with any diet, that there are risks.

Read on to learn more about types of fasting and the benefits versus risks of fasting for people with psoriasis.

Person pouring hot water into a tea cup, fasting for psoriasis. Share on Pinterest
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Problems with the immune system cause psoriasis. This can be due to both genetic and environmental factors.

With this condition, skin cells that normally take a month to turn over do so in a matter of days. On pale skin, it can result in red skin with thick patches of itchy, silvery scales. On dark skin, it can produce purple scaly patches.

Taking a break from eating allows the body to redirect energy used for processing food to cellular repair. Studies are examining whether this can help heal psoriasis.

In a 2019 observational study, researchers followed a group of 37 people with psoriatic arthritis who used fasting from sunrise to sunset for one month during Ramadan. People continued to take their current medications for psoriasis. This study showed that fasting significantly improved disease activity scores, muscle inflammation, and dactylitis, which is inflammation in the fingers. The average weight of the patients did not change during the study.

Another observational study from the same year followed 108 people with stable moderate-to-severe psoriasis during Ramadan. People fasted for 17 hours each day and continued their current medications. Results showed a significant reduction in the Psoriasis Area and Severity Index after the month-long observance period.

Researchers need to conduct more randomized, controlled trials in humans to determine the true treatment benefits of fasting to help manage psoriasis.

Intermittent fasting (IF) refers to several methods of food intake restriction. It is also known as alternate day fasting, reduced meal frequency, or time-restricted eating. The intake on non-fasting days can vary from unrestricted eating to specific forms of calorie reduction. The most common types of IF are:

  • Time-restricted eating: People eat during a limited window each day. This method may or may not involve calorie restriction. Common methods are the 16:8 method, which involves only eating food during 8 hours of the day, and the 12:12 method, which allows eating during 12 hours of the day.
  • Alternate day fasting (ADF): ADF involves severe calorie restriction every other day or on certain days of the week. People do not calorie count on non-fasting days. The most common method is 5:2, where people fast for 2 preferably nonconsecutive days of the week, with normal eating on the other 5 days.
  • Modified alternate day fasting: The method is like ADF, except that on fasting days, meeting 15–25% of total daily energy needs is allowed.

More prolonged fasting methods require that people abstain from all food for 2 days or longer. People only take water on fasting days. This is not a type of IF.

Having psoriasis or psoriatic arthritis increases the risk of developing other conditions such as obesity, type 2 diabetes, and high blood pressure. Studies are looking at ways that treating these other diseases may also positively impact the course of psoriasis.

Weight loss

Some of the research into environmental triggers for psoriasis has focused on diet and body weight.

A recent literature review describes the bidirectional link or two-way, shared connection between psoriasis and obesity. This means that people with obesity have a greater risk of psoriasis and people with psoriasis have a greater risk of obesity.

According to the review, a low calorie diet used for weight reduction in people who are overweight or have obesity can result in reductions in psoriasis severity. There was no conclusion regarding the best diet for weight loss.

IF could potentially lead to weight loss. A 2020 systematic review combined the results of 27 trials and found that weight loss ranged from 0.8 to 13.0% of baseline weight with no serious side effects.

Larger studies with a longer duration are required to fully understand the impact of fasting on sustainable weight loss, general health, and improvements in psoriasis.

The National Institutes of Health (NIH) recommend maintaining a healthy weight to help manage psoriasis.

The medical board of the National Psoriasis Foundation also conducted a systematic review of the literature and strongly recommends weight reduction in people who are overweight and those with obesity who have psoriasis.

Improved glycemic control

Some of the trials included in the 2020 systematic review enrolled people with diabetes. Study authors report that IF shows promise in:

These measures indicate the level of diabetes control to help prevent long-term complications such as heart, eye, kidney, and nerve problems.

Other benefits

Studies have shown improvements in mood and self confidence when using IF. Participants also reported less depression.

The study of fasting is an active area of research. Researchers should verify additional proposed benefits such as reductions in cardiovascular risks, improved cognition, reduced inflammation, and increases in healthy lifespan.

The clinical trials monitored for safety concerns with IF. These include the development of eating disorders, particularly binge eating during non-fasting periods.

There were also reports of:

Certain groups of people should not fast. These include children and adolescents, people who are pregnant or breastfeeding, people older than 75, those with an active infection or diabetes, and people with eating disorders.

It is important to consult a doctor when considering a diet change. The doctor can explain the pros and cons of various diets and help a person determine if fasting for psoriasis is worth a try.

If a person starts fasting, the doctor will monitor any resulting weight loss or changes in psoriasis symptoms and severity. The doctor may make adjustments to dosages of current medications if needed. They will also monitor for any side effects of fasting.

A registered dietician can help with a detailed personalized diet strategy. They are familiar with many types of diets, including fasting.

There is not enough evidence to recommend that people use fasting to help symptoms of psoriasis. Researchers report improvements in psoriasis symptoms and severity with fasting, but only saw these results in small observational studies. Larger, randomized controlled trials are needed to assess the impact of fasting on psoriasis fully.

Some benefits of fasting seen in clinical trials include potential weight loss, improved glycemic control, and improvements in mental outlook. People should weigh these benefits against the risks of hypoglycemia, dizziness, headache, and other potential side effects.

A doctor can help determine if fasting should be part of a person’s strategy to manage psoriasis.