Low-carbohydrate Diet and Low-Density Lipoprotein - Cholesterol (LDL-c) Interindividual Variability (REPETO)
25. června 2026 aktualizováno: Bruno Spellanzon, University of Bath
Exploring True Interindividual Heterogeneity of Cardiovascular Disease (CVD) Risk Factors in Response to Low-carbohydrate Diets Using a Replicate Crossover Randomised Controlled Trial
Ketogenic diets are very low-carbohydrate diets that increase hepatic production of ketone bodies, which have several effects as substrates and signals.
Ketogenic diets are used to manage some conditions (e.g., drug-resistant epilepsy), and their potential for managing many other conditions (e.g., cancer) is being actively explored.
Indeed, the British Dietetic Association acknowledge the potential for ketogenic diets to improve glycaemic control to a greater extent than some other diets in people with type 2 diabetes.
A lower fasting glucose is also relevant to future mortality in people without diabetes.
Ketogenic diets are popular in the general population, with up to 15% of the UK following a low-carbohydrate diet.
There is, therefore, great interest in ketogenic diets amongst people with and without health conditions.
However, although the diet shows promising results in improving blood sugar levels, it has also shown to increase low-density lipoprotein-cholesterol (LDL-c) in some individuals, which has been linked to increased cardiovascular health risks.
The aim of this project is to find the potential for personalised use of (or guidance to avoid) ketogenic diets for cardiovascular disease risk.
To do that the investigators will ask participants to replicate 24 hours of a ketogenic diet and a control diet thrice each.
This will allow the investigators to find variability between responses and have a better idea of individuals who could benefit (or not) from following the ketogenic diet.
Přehled studie
Detailní popis
The study will be a controlled feeding replicate randomised controled trial with 3 cycles, each involving the pair of diets [low carbohydrate (K) and control (C) diets]. There will be 6 x 1-day periods (3 days low carbohydrate and 3 days control). Twenty individuals (body mass index: 18.5-35 kg/m2) will be recruited and randomised into one of the 8 possible sequences:
- KC KC KC
- KC KC CK
- KC CK KC
- KC CK CK
- CK CK CK
- CK CK KC
- CK KC CK
- CK KC KC A week before the interventions start, participants will visit the laboratory so that the investigators can perform indirect calorimetry and collect a blood sample for genotyping. During the week before the interventions, participants will wear activity monitors to determine habitual physical activity. Before each visit, participants will be asked to come to the lab in a rested and overnight fasted state. During the first trial visit, participants will have a dual-energy X-ray absorptiometry (DEXA) body scan to determine body composition. During all 12 study visits the investigators will perform a venepuncture in an antecubital vein and will collect 20 mL of blood.
Additionally, the investigators will also collect urine samples. After odd visits (1st, 3rd, 5th, 7th, 9th and 11th), participants will be supplied with their respective meals for the day (low carbohydrate or control) and will be asked to not eat anything else during the day.
Finally there will be a wash-out period of 6 days between laboratory visits. To keep consistency between trial days, participants will be asked to replicate physical activity levels performed during the 24 hours before the first trial, and during diet day (before second visit), so that these can be replicated for the following visits.
Typ studie
Intervenční
Zápis (Odhadovaný)
20
Fáze
- Nelze použít
Kontakty a umístění
Tato část poskytuje kontaktní údaje pro ty, kteří studii provádějí, a informace o tom, kde se tato studie provádí.
Studijní kontakt
- Jméno: Bruno Spellanzon, PhD candidate
- Telefonní číslo: 447769407954
- E-mail: bs954@bath.ac.uk
Studijní místa
-
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Bath and North East Somerset
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Bath, Bath and North East Somerset, Spojené království, BA2 7AY
- Nábor
- University of Bath
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Vrchní vyšetřovatel:
- Javier Gonzalez, PhD
-
Kontakt:
- Bruno Spellanzon, PhD candidate
- Telefonní číslo: 447769407954
- E-mail: bs954@bath.ac.uk
-
Kontakt:
- Javier Gonzalez, PhD
- E-mail: jg833@bath.ac.uk
-
-
Kritéria účasti
Výzkumníci hledají lidi, kteří odpovídají určitému popisu, kterému se říká kritéria způsobilosti. Některé příklady těchto kritérií jsou celkový zdravotní stav osoby nebo předchozí léčba.
Kritéria způsobilosti
Věk způsobilý ke studiu
- Dospělý
- Starší dospělý
Přijímá zdravé dobrovolníky
Ano
Popis
Inclusion Criteria:
- Age: >18 years
- Body mass index: 18.5-35 kg·m-2
- Low-Density Lipoprotein-cholesterol <4.9 mmol/L
- Non-fasting triglycerides <2.3 mmol/L
Exclusion Criteria:
- weight instability (>5% change in body mass within last 3 months)
- smoker
- diagnosis of hypercholesterolaemia or any other lipid-related disease
- diagnosis of diabetes
- diagnosis of atherosclerotic cardiovascular disease
- elevated fasting glucose (>5.4 mmol/L)
- dietary intolerances or allergies or to other study procedures
- diagnosis of gastrointestinal disorders
- any other condition/medication that could introduce bias to the study
- already following a ketogenic diet
- not willing to follow a ketogenic diet
- unable to understand English language
Studijní plán
Tato část poskytuje podrobnosti o studijním plánu, včetně toho, jak je studie navržena a co studie měří.
Jak je studie koncipována?
Detaily designu
- Primární účel: Základní věda
- Přidělení: Randomizované
- Intervenční model: Crossover Assignment
- Maskování: Žádné (otevřený štítek)
Zbraně a zásahy
Skupina účastníků / Arm |
Intervence / Léčba |
|---|---|
|
Jiný: Sequence 1
Participants will follow a 1) low-carbohydrate diet, wash-out, 2) control diet, wash-out, 3) low-carbohydrate diet, wash-out, 4) control diet, wash-out, 5) low-carbohydrate diet, wash-out, 6) control diet
|
Diet will have macronutrients split with 50% carbohydrates, 15% protein and 35% fat.
Also there will be a 0.66 ratio saturated:unsaturated fat
Diet will have macronutrients split with 8% carbohydrates, 15% protein and 77% fat.
Also there will be a 0.66 ratio saturated:unsaturated fat
|
|
Jiný: Sequence 2
Participants will follow a 1) low-carbohydrate diet, wash-out, 2) control diet, wash-out, 3) low-carbohydrate diet, wash-out, 4) control diet, wash-out, 5) control diet, wash-out, 6) low-carbohydrate diet
|
Diet will have macronutrients split with 50% carbohydrates, 15% protein and 35% fat.
Also there will be a 0.66 ratio saturated:unsaturated fat
Diet will have macronutrients split with 8% carbohydrates, 15% protein and 77% fat.
Also there will be a 0.66 ratio saturated:unsaturated fat
|
|
Jiný: Sequence 3
Participants will follow a 1) low-carbohydrate diet, wash-out, 2) control diet, wash-out, 3) control diet, wash-out, 4) low-carbohydrate diet, wash-out, 5) control diet, wash-out, 6) low-carbohydrate diet
|
Diet will have macronutrients split with 50% carbohydrates, 15% protein and 35% fat.
Also there will be a 0.66 ratio saturated:unsaturated fat
Diet will have macronutrients split with 8% carbohydrates, 15% protein and 77% fat.
Also there will be a 0.66 ratio saturated:unsaturated fat
|
|
Jiný: Sequence 4
Participants will follow a 1) low-carbohydrate diet, wash-out, 2) control diet, wash-out, 3) control diet, wash-out, 4) low-carbohydrate diet, wash-out, 5) low-carbohydrate diet, wash-out, 6) control diet
|
Diet will have macronutrients split with 50% carbohydrates, 15% protein and 35% fat.
Also there will be a 0.66 ratio saturated:unsaturated fat
Diet will have macronutrients split with 8% carbohydrates, 15% protein and 77% fat.
Also there will be a 0.66 ratio saturated:unsaturated fat
|
|
Jiný: Sequence 5
Participants will follow a 1) control diet, wash-out, 2) low-carbohydrate diet, wash-out, 3) control diet, wash-out, 4) low-carbohydrate diet, wash-out, 5) control diet, wash-out, 6) low-carbohydrate diet
|
Diet will have macronutrients split with 50% carbohydrates, 15% protein and 35% fat.
Also there will be a 0.66 ratio saturated:unsaturated fat
Diet will have macronutrients split with 8% carbohydrates, 15% protein and 77% fat.
Also there will be a 0.66 ratio saturated:unsaturated fat
|
|
Jiný: Sequence 6
Participants will follow a 1) control diet, wash-out, 2) low-carbohydrate diet, wash-out, 3) control diet, wash-out, 4) low-carbohydrate diet, wash-out, 5) low-carbohydrate diet, wash-out, 6) control diet
|
Diet will have macronutrients split with 50% carbohydrates, 15% protein and 35% fat.
Also there will be a 0.66 ratio saturated:unsaturated fat
Diet will have macronutrients split with 8% carbohydrates, 15% protein and 77% fat.
Also there will be a 0.66 ratio saturated:unsaturated fat
|
|
Jiný: Sequence 7
Participants will follow a 1) control diet, wash-out, 2) low-carbohydrate diet, wash-out, 3) low-carbohydrate diet, wash-out, 4) control diet, wash-out, 5) control diet, wash-out, 6) low-carbohydrate diet
|
Diet will have macronutrients split with 50% carbohydrates, 15% protein and 35% fat.
Also there will be a 0.66 ratio saturated:unsaturated fat
Diet will have macronutrients split with 8% carbohydrates, 15% protein and 77% fat.
Also there will be a 0.66 ratio saturated:unsaturated fat
|
|
Jiný: Sequence 8
Participants will follow a 1) control diet, wash-out, 2) low-carbohydrate diet, wash-out, 3) low-carbohydrate diet, wash-out, 4) control diet, wash-out, 5) low-carbohydrate diet, wash-out, 6) control diet
|
Diet will have macronutrients split with 50% carbohydrates, 15% protein and 35% fat.
Also there will be a 0.66 ratio saturated:unsaturated fat
Diet will have macronutrients split with 8% carbohydrates, 15% protein and 77% fat.
Also there will be a 0.66 ratio saturated:unsaturated fat
|
Co je měření studie?
Primární výstupní opatření
Měření výsledku |
Popis opatření |
Časové okno |
|---|---|---|
|
Fasted plasma Low-density lipoprotein cholesterol (LDL-C) concentrations
Časové okno: Pre and post following each intervention/control diet for 24 hours
|
Variable will be used to establish whether there is true inter-individual heterogeneity in response to 24 hours of a low-carbohydrate diet. Measured in mmol/L. |
Pre and post following each intervention/control diet for 24 hours
|
Sekundární výstupní opatření
Měření výsledku |
Popis opatření |
Časové okno |
|---|---|---|
|
Fasted glucose plasma glucose concentration
Časové okno: Pre and post following each intervention/control diet for 24 hours
|
Variable measured to establish whether there is true inter-individual heterogeneity in response to 24 hours of a low-carbohydrate diet. Measured in mmol/L |
Pre and post following each intervention/control diet for 24 hours
|
Spolupracovníci a vyšetřovatelé
Zde najdete lidi a organizace zapojené do této studie.
Sponzor
Vyšetřovatelé
- Vrchní vyšetřovatel: Javier Gonzalez, PhD, University of Bath
Termíny studijních záznamů
Tato data sledují průběh záznamů studie a předkládání souhrnných výsledků na ClinicalTrials.gov. Záznamy ze studií a hlášené výsledky jsou před zveřejněním na veřejné webové stránce přezkoumány Národní lékařskou knihovnou (NLM), aby se ujistily, že splňují specifické standardy kontroly kvality.
Hlavní termíny studia
Začátek studia (Aktuální)
5. února 2026
Primární dokončení (Odhadovaný)
1. března 2027
Dokončení studie (Odhadovaný)
1. března 2027
Termíny zápisu do studia
První předloženo
5. května 2026
První předloženo, které splnilo kritéria kontroly kvality
25. června 2026
První zveřejněno (Aktuální)
30. června 2026
Aktualizace studijních záznamů
Poslední zveřejněná aktualizace (Aktuální)
30. června 2026
Odeslaná poslední aktualizace, která splnila kritéria kontroly kvality
25. června 2026
Naposledy ověřeno
1. června 2026
Více informací
Termíny související s touto studií
Další relevantní podmínky MeSH
Další identifikační čísla studie
- 8791-12081
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