Inclusion criteria (First phase):
* Individuals who regularly eat meat (4 portions of meat per week for at least 2 months prior to enrolment in the study).
* Aged 18 and older.
* Body Mass Index (BMI) between 18.5 - 30 kg/m2.
* Living within 40 miles from the Norwich Research Park.
Inclusion criteria (Second phase)
* meets first phase inclusion criteria
* TMAO producer (plasma TMAO increase of \>5 µM and \>50% after L-carnitine ingestion.
Exclusion criteria:
* Consume an entirely vegan, vegetarian, or pescatarian diet within the last two months.
* Do not have access to a freezer to store some provided meals and ice packs.
* Have a known allergy to the tablets, capsules (i.e., pomegranate), or standardised meals such as wheat, eggs, milk, nuts, and soybeans.
* Have difficulty swallowing, a swallowing disorder, or are unable to swallow four capsules (the size of a peanut) and three L carnitine tablets consecutively within a time span of ten minutes.
* Have bowel movements less than five times a week.
* Are a current smoker (or stopped smoking for less than 3 months).
* Consume more than 14 units of alcohol per week (for example, a pint of beer or a 175 mL glass of wine each count as two units).
* Are pregnant or breastfeeding.
* Have anaemia or any conditions or medications that may hinder clotting. This will be assessed on a case-by-case basis.
* Have high or low blood pressure (i.e., ≤90/60 or ≥160/100 mmHg).
* Have a medical condition or take medications that may affect the primary outcome of this study, such as but not limited to diabetes, liver disease, hypo/hyperthyroidism, or fish odour syndrome. This will be assessed on a case-by-case basis.
* Have had gastrointestinal disease or surgical procedures that may affect the primary outcome of this study. This will be assessed on a case-by-case basis.
* Have known or a history of kidney disease, this will be determined by the medical advisor using blood urea nitrogen and creatinine levels in the participant's blood.
* Regularly use bowel cleansing techniques like colonic irrigation or laxatives.
* Had an infection or received antibiotics within a month prior to this study.
* Regularly take dietary supplements that may affect the primary outcome measure of this study, such as fish oil or L carnitine supplements.
* Are currently undergoing active treatment for cancer or heart disease.
* Participated in another dietary intervention study within the last four months.
* Have donated a large quantity of blood within the last 16 weeks. Registered donors should abstain from blood donations for the duration of the study.
* Are a person related to or living with a member of the study team.
* Are unable to give written or verbal informed consent.
* Participant is unable to provide GP (General Practitioner) contact details.
* Have symptoms of Coronavirus infection (COVID-19), been asked to self-isolate, or have been diagnosed with COVID-19 in the last 14 days.
