THE WHY?

What are the inclusion criteria?  

• You must be an adult (18 years of age or older). 

• You must have a medical diagnosis of plaque psoriasis. 

• You have a baseline Psoriasis Area Severity Index score between 5-10 (evaluated during screening).  

• A body mass index between 20-40.   

• You are not on tablet or injection therapies for psoriasis, or if you are on tablet or injection therapies, you are 6 months stable on the same dose of tablet or injection therapies

 

What are the exclusion criteria?  

You will not be able to participate if you:

• are a minor (< 18 years old). 

• are not diagnosed with psoriasis.

• have a body mass index of < 20.00 or above 40.99.

• are taking Cyclosporine or Stelara in the past 3 months.

• are receiving or have received photo (light) therapies for psoriasis in the past 3 months 

• are a shift worker or involved in shift work. 

• are planning international travel during the study period. 

• are diagnosed with a gluten, nut, peanut, fish or shellfish allergy.

• are diagnosed with a gluten or dairy intolerance.  

• are following a restrictive diet or restricting food groups i.e vegan, vegetarian, gluten-free or a Mediterranean style diet.  

• are following any of the intermittent fasting regimes inclusive of 5:2, alternate day fasting, modified alternate day fasting or time-restricted eating over the past 6 months.  

• report a habitual eating window <12 hours per day.

• are not weight stable or have attempted to lose weight over the past 6 months. 

• are taking fish oil or other dietary supplements (except daily multivitamins providing no more than 200% of UK dietary recommended values). 

• are pregnant, currently breastfeeding or planning to become pregnant in the next 4 months. 

• have been diagnosed with: 

  • Anaemia 

  • Asthma 

  • Cancer in the last five years (except non-melanoma skin cancer) 

  • Cardiovascular disease (angina, congenital heart disease, coronary artery disease, heat attack, heart failure or stoke) 

  • Chronic gastrointestinal disease (Crohn's disease, ulcerative colitis, celiac disease or malabsorption diseases) 

  • Chronic kidney disease 

  • Dementia 

  • Eating disorders (anorexia, bulimia or binge eating disorder) 

  • Insulin dependent diabetes 

  • Liver disease 

  • Lupus 

  • Multiple sclerosis 

  • Rheumatoid arthritis 

  • Thyroid disease 

• have history of bariatric surgery.  

• have a history of substance abuse or alcoholism (past history of alcohol intake >60 units/men or 50 units/women). within the last 12 months. 

• are taking medication likely to interfere with study outcomes e.g. steroids (except occasional use of inhalers), anti-inflammatories or immune-suppressive drugs. 

• have not been on a stable dose of blood pressure medication for the past 3 months (if prescribed). 

• are not on a stable topical treatment regimen for psoriasis (if prescribed).

• are currently participating in a pharmaceutical study for psoriasis treatments (topical, light, tablet or injection) or have participated in a pharmaceutical study less than 3 months ago.

• are currently participating in another diet intervention study or have participated in a diet intervention study < 3 months ago.  

• are NOT willing to record your dietary intakes using handwritten diet diaries.   

• are NOT fluent in the English language.

• report to have fainted in the past during an intravenous blood test.

 

Do I have to take part?  

• Participation is completely voluntary.  

• You should only take part if you want to. 

• Choosing not to take part will not disadvantage you in any way.

• The Psoriasis Association will not be made aware of your participation in the study. 

• If you choose to participate, you will be asked to provide your consent . 

 

We encourage you to contact the research team through the  Contact page, if you have any questions about participating.

 

How do I enrol in the METRED-P study?  

You will be enrolled in the study if all the study criteria are met during the screening process.

 

What is the screening process? 

• You will first be asked to read an information sheet.

• If the study is of interest, you will have an initial video call with the Research Nutritionist. 

• You will then be invited to an online video consultation with the Research Nutritionist and Consultant Dermatologist.

• If the initial inclusion criteria are met, you will be invited to attend a screening clinic visit (45-60 minutes) where you will be asked to provide written informed consent to participate in the study. 

• Upon providing informed consent, you will have a brief medical examination (weight, height, blood pressure), a psoriasis assessment and a fasted blood sample will be collected. 

• The results of the clinic visit will be reviewed by the Consultant Dermatologist, and once approved, you will be able to start the METRED-P study. 

 

What is the video call? 

The initial video call is a brief call with the Research Nutritionist. This call will be hosted over Microsoft Teams, in confidentiality, and will not be recorded.

​

During the call: 

• the information sheet will be reviewed with you.

• the informed consent process will be reviewed you. 

• you will be asked general questions on your characteristics, aspects of your diet, and general health.

 

This call is your opportunity to ask questions and address any aspects of the study requiring clarifications.  

​

What is the online video consultation? 

The online video consultation call is a call with the Research Nutritionist and Consultant Dermatologist. This consultation will be hosted over Microsoft Teams, in confidentiality, and will not be recorded.

 

During the consultation: 

• You will be asked questions on your diet characteristics. 

• The Consultant Dermatologist will examine your psoriasis with the Psoriasis Area Severity Index. 

 

How will the Consultant Dermatologist examine my psoriasis during the video consultation? 

You will need to show the parts of your body affected by psoriasis to the Consultant Dermatologist via the web cam, who will note down scores for severity by assessing the thickness, redness, scaliness and the areas affected by psoriasis. 

 

How long do I have to decide if I want to continue with the study? 

There is no time limit given to decide whether you wish to participate.  

​

Where does the clinic visit take place? 

All clinic visits will take place at the Metabolic Research Unit on the 4th Floor (Corridor A), in the Franklin Wilkins Building, King’s College London: 150 Stamford Street, SE1 9NH, only 5 min from Waterloo station. 

 

How do I attend the clinic visits? 

• All clinic visits must be attended in a fasted state. This means food should be consumed for up to 12 hours before the clinic visit, after which you should abstain from food intake. 

• Plenty of water should be consumed as normal.

• Alcohol and caffeine should be avoided for the previous 12 hours. 

• Strenuous exercise should be avoided for the previous 24 hours. 

 

How do I provide informed consent? 

Informed consent is obtained in writing. To provide informed consent, you will need to indicate that you have read and understood the information sheet provided and that you consent to your data being used for the purposes explained.​ This is achieved by: 

 

• Ticking all the statements on the consent form. 

• Signing and dating the consent form.  

• The Research Nutritionist countersigning and dating the consent form and providing you with a copy of the signed form. 

 

Can I participate without providing informed consent? 

You will NOT be able to participate in the study without providing informed consent. 

 

What is the screening clinic visit? 

The purpose of the screening visit is to ensure you are fit to participate in the study. At the visit you will: 

• Read the information sheet. 

• Provide informed consent. 

• Have a psoriasis examination by the Consultant Dermatologist. 

• Have your body composition measured using the TANITA step on scale.  

• Have your weight, height, waist circumference, hip circumference measured by the Research Nutritionist. 

• Have your clinic blood pressure measured by the Research Nutritionist. 

• Have a fasting blood sample taken by a Paramedic. 

• Receive guidance on how to record your pre-study 4-day diet diary. 

 

What if I am not eligible to participate in the study?

If you are ineligible to participate in the study, you will receive an email with a justification provided as to why. The email will also contain contact details should you wish to have further clarifications. If all the study criteria are met during the screening process, you are eligible to enrol in the METRED-P study. 

 

How will I know if I am eligible to participate in the study? 

If you are eligible to participate in the study, within 3 weeks of the screening visit, you will be informed by telephone and by email. Arrangements will be made to schedule your study dates including the initial and final clinic visits. You will receive a confirmation email with the agreed dates.  

 

How long does the METRED-P study last? 

The METRED-P study lasts approximately 14 weeks, when accounting for the screening procedures (initial call, video consultation and screening visit). The diet intervention phase of the study lasts a total of 85 days (12 weeks). 

 

What does the METRED-P study consist of? 

(see study flowchart)

An initial clinic visit (Day 0). 

 

Week 1 (day 1 - day 7):  record your 4-day diet diary.   

  

Week 2: well-being call with the Research Nutritionist (15 minutes).

   

Week 4 (day 28) you:  

• will have a virtual diet consultation booster session with the Research Nutritionist (45-60 minutes).  

• will be asked to weigh yourself and disclose your weight to the Research Nutritionist.

• will be asked to complete: 

• The self-assessed - Psoriasis Area Severity Index (2 minutes) . 

• The Dermatology Life Quality Index (2 minutes) . 

• The World Health Organisation - 5 survey (1 minute) . 

  

Week 6 (day 36- day 42): record your 4-day diet diary.  

Week 6: well-being call with the Research Nutritionist (15 minutes).

 

Week 8 (Day 56) you:  

• will have a virtual diet consultation booster session with the Research Nutritionist (45-60 minutes). 

• will be asked to weigh yourself and disclose your weight to the Research Nutritionist. 

• will be asked to complete: 

• The self-assessed - Psoriasis Area Severity Index (2 minutes).  

• The Dermatology Life Quality Index (2 minutes) . 

• The World Health Organisation - 5 survey (1 minute).  

  

Week 10: well-being call with the Research Nutritionist (15 minutes).

  

Week 12 (day 78 - day 84): record your 4-day diet diary . 

   

Final clinic visit (day 85) : repeat the measurements obtained at the first clinic visit and provide a fasted blood sample.

 

What happens at the first clinic visit? 

A Paramedic  will take a blood sample (approximately 3 teaspoons of blood) from a vein in your arm.  

​

A Consultant Dermatologist will assess the severity of psoriasis using: 

• the Psoriasis Area Severity Index, which examines the area, thickness, redness and scaliness of your psoriasis. 

• the Physician Global Assessment, evaluating the thickness, redness and scaliness of your psoriasis. 

 

You: 

• will be asked to complete the self - assessed Simplified Psoriasis Index (2 minutes). This is a self-evaluation of the severity of your psoriasis. 

• will be asked to complete the Dermatology Life Quality Index (2 minutes). This is to evaluate the impact of your psoriasis on day-to-day activities.  

• will be asked to complete The World Health Organisation, WHO-5 survey (1 minute). This is to assess your overall state of wellbeing.  

 

The Research Nutritionist:  

• will take weight, waist and hip circumference measurements.  

• will record your body composition measures from TANITA* .

• will take clinic blood pressure measurements (3 repeat measurements). 

• will review your pre-study 4-day diet diary. 

• will lead a diet consultation session on your allocated diet. This session will be supplemented with information documents including dietary guidelines, serving size manuals, meal plans and recipes to follow at home, a food swap and a shopping list, eating out and  budget-eating advice sheets.

  

*TANITA is a step-on scale that provides a body composition analysis. You will need to take your shoes and socks or tights off for this. The duration is 1 minute.  

 

How will the fasting blood sample be taken? 

The fasting blood sample will be taken by a Paramedic using a butterfly needle that will be inserted in a vein in your arm. 

 

How many fasting blood samples will be taken? 

One fasting blood sample will be taken at the screening visit, one fasting blood sample will be taken at the initial clinic visit and one fasting blood sample will be taken at the final clinic visit. There are in total 3 fasted blood samples. 

 

How much blood will be taken? 

At the screening visit, approximately 13 mL will be taken (3.5 teaspoons). 

At the initial visit, approximately 12 mL will be taken (3 teaspoons). 

At the final visit, approximately 12 mL will be taken (3 teaspoons). 

 

What will the fasting blood sample measure?  

The fasting blood sample from the screening clinic visit will measure blood glucose and fats, liver function and the full blood counts. 

The fasting blood sample from the initial and final clinic will measure blood glucose and fats, insulin, high-sensitivity c-reactive protein and inflammatory molecules.

 

What happens if I faint during the fasting blood sample? 

There is a medical professional on site and should fainting occur, you will receive all the medical assistance required and you will be cared for until you are fit to leave the Metabolic Research Unit.  

 

If I faint during the fasting blood sample, will I still be able to participate in the study? 

• Should fainting occur during the fasting blood sample at the screening clinic visit, you would not be proceeding with the study.

• Should fainting occur during the fasting blood sample at the initial clinic visit, the medical professional will decide if you are fit to continue with the study and/or future studies. 

​

What happens during the psoriasis examination? 

You will need to show the parts of your body affected by psoriasis to the Consultant Dermatologist who will note down the severity by scoring the thickness, redness, scaliness and the areas affected by psoriasis. 

 

What is the Dermatology Life Quality Index (DLQI)? 

The DLQI is a multiple-choice survey with 10 questions on the social and psychological impact of psoriasis on day-to-day activities.  

 

What is the self-assessed Simplified Psoriasis Index (sa-SPI)? 

The sa-SPI is a 3-component survey with questions on your skin, the psychosocial impact of psoriasis, and your treatment history for psoriasis.

 

What is the World Health Organisation-5 survey? 

The WHO-5 is a 5-question multiple choice survey on well-being. 

 

When do I complete the sa-SPI, DLQI and WHO-5, surveys?  

You will complete the  sa-SPI, DLQI and WHO-5, at the initial and final clinics and on day 28 and on day 56 of the study. 

​

Where do I complete the sa-SPI, DLQI and WHO-5? 

These assessments will be completed as an online survey. 

For the day 28 and day 56 surveys, the survey link will be emailed to you by the Research Nutritionist.

 

How will my clinic blood pressure be measured? 

Clinic blood pressure will be measured with a sphygmomanometer. A cuff will be wrapped around your upper arm (above the elbow) and will inflate for a few seconds and then deflate.  

 

What are the diet groups in the study? 

The three diets groups are: 

1. UK diet with time-restricted eating  

2. Mediterranean style diet 

3. Mediterranean style diet with time restricted eating   

 

What do I record in my 4-day diet diary? 

All food and drink items (and their quantities!) consumed during the day should be recorded. You should record your diary during the course of the day, not from memory at the end of the day. The diet-diaries also ask you to record your sleep/wake times and physical activity for these days. 

 

On what days do I record the 4-day diet diary? 

The 4-day diet diary should be completed to represent 3 weekdays and 1 weekend day e.g. Monday, Tuesday, Friday & Sunday. The days do NOT need to be consecutive. 

 

Where do I record my 4-day diet diary? 

You will be provided with 3 sets of diet diaries, one for each assigned week i.e Week 1, Week 6, and Week 12. Each set will contain 4 days of diet diary space to complete in writing. 

 

When do I record my 4-day diet diaries? 

You will record your diet diaries on Week 1, Week 6, and Week 12.  

 

Why do I need to record my intake on 4-day diet diaries? 

Your food and beverage intake will need to be recorded such that we can review your progress with adhering to your assigned diet and set dietary goals to revise during the virtual diet consultation sessions. 

 

Are instructions provided on how to complete the 4-day diet diary? 

The Research Nutritionist will guide you through the recording of the 4-day diet diary at your screening visit. An instruction booklet with guidance on how to complete diet diaries will be provided to all the participants.  

 

What if I can’t complete my 4-day diet diary during the course of the day? 

Please keep a small note of your food and drink intake (and quantities) on a notepad or phone. When you have time at the end of the day, return to your diet diary and write up your food and drink intakes in the 4-day diet diary booklet.

 

What are the well-being calls? 

These calls are set up with the Research Nutritionist  who will check on your general well-being and are your opportunity to ask any questions and address any concerns. 

 

What are the diet consultations sessions? 

These sessions are 1:1 consultations with the Research Nutritionist (who is a AfN Associate Registered Nutritionist).These sessions will be hosted on Microsoft Teams, will last approximately 45-60 minutes, and will not be recorded. Dietary guidelines will be revised and the set weekly goals will be reviewed. Additional goals will be set for the subsequent diet consultation sessions. The diet consultation session is also the space for you to raise issues in relation to adherence to the diet, which will be taken into consideration by the Research Nutritionist, who will also check that you are completing the required at home study tasks.

 

Will I receive support documents to assist me with the assigned diet? 

You will receive information documents including a dietary guideline booklet, a serving size manual, meal plans and recipes to follow at home,  a food swap sheet, a shopping list, eating out advice and budget-eating advice.

 

What if I am unable to adhere to the dietary advice? 

If you are unable to adhere to the dietary advice, please contact the Research Nutritionist who will arrange a consultation session to address your concerns. It is important to keep recording your food and drink intakes in your diet diary as you normally would, even if your intakes do not comply with your allocated diet. This is such that the Research Nutritionist can revise your diet and suggest changes to best proceed with the study. 

 

What happens at the final clinic visit? 

The final clinic visit is a repeat of the first clinic visit without the diet consultation session. 

​

What do I need to do to successfully complete The METRED-P Study? 

To successfully complete the METRED-P study you will need: 

• To attend all three clinic visits for the fasting blood sample, psoriasis examination, body composition measurements and complete the psoriasis questionnaires. 

• Participate in three well-being calls (on Week 2, Week 6 and Week 10).  

• Participate in two diet consultation sessions (on Week 4 and Week 8).  

• Complete all 4-day diet diaries (Week 1, Week 6 and Week 12).  

• Complete the psoriasis questionnaires (on Week 4 and Week 8). 

• Complete an exit questionnaire (at the final clinic visit).

 

What device should I use to complete the online psoriasis questionnaires? 

It is best to complete the psoriasis questionnaires on a laptop or desktop computer for the questions to fully display.

​

What happens if I close my browser window when completing the online psoriasis questionnaires? 

If you close your browser window and return to that same link, on the same browser and on the same device, you will be able to resume where you left off, provided you haven't deleted browsing history and/or cookie/data. 

​ 

Who is the sender of the email containing the psoriasis questionnaires? 

dietandpsoriasisproject@kcl.ac.uk 

 

Are there any incentives for taking part in The METRED-P Study? 

With the completion of The METRED-P Study you will receive:  ​

• A £100 remuneration. 

• Travel expenses will be reimbursed up to £20 per clinic visit.  

 

What are the possible risks of taking part?  

 Blood test:  

• You may feel an initial sharp scratch sensation on your arm with the insertion of the needle for the blood sample.   

• You may experience minor bleeding on the area where the needle was inserted. This will be covered with a bandage to minimise the bleeding and reduce skin exposure.  

• There may be minor bruising and/or irritation on the skin. This is normal and will typically last 2-3 days.  

• Your arm may feel sore. This is normal and will typically last 1-2 days.  

• During and/or after the blood sample, you may feel dizzy and/or faint. If this has happened in the past, we advise you to inform the clinician conducting the blood test so that they are aware.  

• Should fainting occur, you will receive all the medial care required until you are fit to leave the Metabolic Research Unit.   

 

Diet intervention:  

• With a change in diet, you may experience some bloating and nausea.   

• Rarely, you may also experience diarrhoea or vomiting.   

​​

 Please report any adverse effects immediately to the research team. The Registered Dietitian will evaluate your symptoms, and will provide assistance and guidance on if and how is best to continue. Should symptoms require medical attention, you will be advised to contact your General Practitioner and you will be withdrawn from the study.

​

Dermatology Life Quality Index: 

The Dermatology Life Quality Index (DLQI) will ask questions on the extent that psoriasis impacts your day-to-day activities. This survey will be completed at the initial and final clinic visits, as well as on Week 4 and Week 8 of the study. The DLQI asks a question on the extent to which the skin has caused any sexual difficulties. It also asks if the skin has created problems with partners or any close friends or relatives. 

​

The DLQI will be completed as an online survey on Qualtrics. At the initial and final clinic visit, participants will complete the DLQI independently on a university laptop, and the responses are confidential.   

 

Support information is provided at the end of the DLQI should any distress arise from answering the survey. 

 

Incidental findings: 

Should blood tests result out of range or if a medical condition is discovered, you will be informed by email and will be advised to contact your General Practitioner. You will be asked to consent to receive a letter addressed to your General Practitioner with a copy of your blood results/skin examination. Upon providing consent, the Consultant Dermatologist will provide you with a letter addressed to your General Practitioner with a copy of your blood results/skin examinations, for you to show your General Practitioner.

​

What if the METRED-P study has resulted in distress? 

Please contact the research team at dietandpsoriasisproject@kcl.ac.uk if participation in the METRED-P study has resulted in significant distress. 

​

Should you wish to receive additional support or information, we encourage you to talk with a GP, Dermatologist, Rheumatologist or another health care professional.   

​

Further information and support on psoriasis can be found on https://www.psoriasis-association.org.uk/   

 

What are the possible benefits of taking part?  

This study is your opportunity to participate in the first clinical study ever to explore the effect of a Mediterranean style diet and time-restricted eating patterns in people living with psoriasis. You will receive information about your health (body composition, clinic blood pressure, blood fats, sugars, liver function and blood cells) and diet and lifestyle advice from a Registered Associate Nutritionist. You may feel an improvement in your general wellbeing.   

 

Will I receive a summary of the findings? 

If you wish to receive a summary of the findings, you will need to tick the box on the informed consent form next to the statement "I wish to receive a copy of the final report".

 

What will happen to the results of the project?  

The results of this project are intended to be submitted for publication within journals in the field of Dermatology and Nutrition and presented at the associated medical and nutrition conferences. This study will be submitted as part of a PhD thesis.  

  

Once the study is completed, we will be sharing the findings with the participants who indicated that they wished to receive a copy of the final report. The findings will be also shared with the Psoriasis Association and on social media and will be used to submit future research grant applications on this topic.  

  

The anonymised data set will be made available in open access journals within 12 months of publication.  

 

What if I change my mind about taking part in the study? 

You are free withdraw at any point of the project, without having to give a reason. Withdrawing from the project will not affect you in any way. You are able to withdraw your data from the project up until August 2024, after which withdrawal of your data will no longer be possible because the data will have been anonymised and committed to the final report. If you choose to withdraw from the project, we will not retain the information you have given thus far.  

  

Please note, should you lose the ability to provide consent during the study, you will be withdrawn from the study. Your data and blood sample already collected with consent would be retained and used in the study. No further data or blood would be collected from you, and neither would any other research procedure be conducted on you. 

 

To withdraw from the METRED-P study please contact the research team at dietandpsoriasisproject@kcl.ac.uk.  

 

How is the study being funded? 

This project is funded by the Psoriasis Association.  

The Psoriasis Association  
Dick Coles House  
2 Queensbridge  
Northampton  
NN4 7BF  

 

mail@psoriasis-association.org.uk  

https://www.psoriasis-association.org.uk/ 

​ 

How will my data be handled? 

Your data will be processed under the terms of UK data protection law (including the UK General Data Protection Regulation (UK GDPR) and the Data Protection Act 2018).   

  

• All the information collected during the clinic visits including patient forms, body measurements, blood analyses and survey responses will be kept confidential. All the dietary information collected during the at home phase will also be kept confidential. The data collected from the METRED-P study will be stored in anonymised form securely on the King’s College London intranet platform and handled in line with the data protection guidelines.  

• The principal investigator is responsible for handling and storing the data during and after the study.  

• The personal details provided (your forename, last name, date of birth, email, home, and GP addresses) will be removed from analysis and your data will be de-identified.  

• No participant will be personally identified in any report or publication.  

• Research data will be retained for a maximum of ten years on completion of the study. This is in accordance with the King’s College London Records and Data Retention Schedule.  

• The study data will remain identifiable for 5 years should participants contact the research team in future and ask for blood tests or psoriasis examination results.   

• The data will only be shared within the research team.   

• Strictly only the research team will have access to the data.  

• The data will not be shared outside of the UK.  
    

Data Protection Statement   

If you would like more information about how your data will be processed under the terms of UK data protection laws, please visit the link below:  

  

https://www.kcl.ac.uk/research/support/research-ethics/kings-college-london-statement-on-use-of-personal-data-in-research