Gestational DiabetesNutcrackerNCT07069855
Nutcracker: Can Almond Nut Consumption Improve Nocturnal Glycaemic Control in Women With Gestational Diabetes Mellitus?
A study testing Almond Snack Intervention for Gestational Diabetes in people with Gestational Diabetes, run by Guy's and St Thomas' NHS Foundation Trust.
Trial summary
Gestational diabetes, affecting over one in six births globally, is a growing public health concern. Characterised by high blood glucose, it increases the risk of pregnancy complications and raises the mother's long-term risk of type 2 diabetes. Read more about this study
- Who is it for?
- Ages 16 to 55 years, women only
- Conditions the study is for
- Gestational Diabetes
- What is being tested?
- Almond Snack Intervention for Gestational Diabetes
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 156 participants
- Where
- No sites listed yet
- Study dates
- Dec 2026to Dec 2027
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 16 to 55 years
- Women only
- No healthy volunteers
- Child, Adult
Who may be able to join
- Age over 16 years
- Singleton pregnancy
- 25 to 31+6 weeks' gestation diagnosed with GDM using a standard clinical 75g oral glucose tolerance test (OGTT), as per the guidelines of the National Institute of Health and Care Excellence (NICE), and had their first post-diagnosis consultation (approx. 7-10 days later). The NICE criteria state that the diagnosis of GDM will be made with one or more glucose concentrations during the OGTT of >5.6 mmol/l in the fasting state; >7.8 mmol/l 2 hours after 75g glucose
- Planned antenatal care at the same centre
- GDm-Health (a digital app for the management of diabetes in pregnancy) used as part of their management for GDM
- Willing and able to give informed consent
Who cannot join
- Age under 16 years or over 55 years
- Multiple pregnancy
- Non-snack consumers
- Smokers
- Women who would work night shifts over the study period
- Women who have already commenced insulin for the treatment of GDM
Show all 9Show fewer
- Allergy or intolerance to nuts
- Pre-existing medical conditions, including Type 1 or Type 2 diabetes, chronic coronary, renal or bowel disease or history of cholestatic liver disease or pancreatitis. Presence of gastrointestinal disorder or use of a drug which is likely to alter gastrointestinal motility or nutrient absorption, previous bariatric surgery
- Unwilling or unable to give informed consent
Trial locations and contacts
No sites are listed yet. Contact the study team or a site near you to ask about taking part.
Olivia Righton contact
About this study
Official title: Nutcracker: Can Almond Nut Consumption Improve Nocturnal Glycaemic Control in Women With Gestational Diabetes Mellitus? A Randomised Controlled Trial
Gestational diabetes, affecting over one in six births globally, is a growing public health concern. Characterised by high blood glucose, it increases the risk of pregnancy complications and raises the mother's long-term risk of type 2 diabetes. Managing high fasting glucose, which reflects elevated overnight levels, is a key challenge. Night-time snacking-more common in women with gestational diabetes-is linked to higher fasting glucose, but the impact of snack quality is unclear. Almonds have been shown to improve glucose control in non-pregnant adults. This study will test whether almonds, as a night-time snack, can improve overnight glucose levels in pregnant women with gestational diabetes. Findings could support a simple, effective dietary strategy to improve outcomes for mothers and babies worldwide.
Read the detailed description
Gestational diabetes mellitus (GDM) is a significant and increasingly prevalent public health concern, affecting over one-sixth of births globally. A key challenge in its management is fasting hyperglycaemia, which may result from elevated nocturnal glucose concentrations. Nocturnal hyperglycaemia has been linked to an increased risk of large-for-gestational-age infants in women with GDM. These women are also more likely to snack at night, a behaviour associated with higher fasting glucose concentrations; however, the impact of snack quality on overnight glucose regulation remains unclear.
Almond consumption has been shown to improve glycaemia in individuals with prediabetes or type 2 diabetes, potentially through mechanisms such as carbohydrate displacement and the beneficial effects of their nutrient profile, particularly magnesium and monounsaturated fats. Despite this, research in pregnant populations-especially those with GDM-is limited.
This study will investigate whether consuming almonds as an evening snack for four weeks improves overnight glucose regulation in women with GDM. Participants will be randomised to receive either almonds or a nut-free, energy-matched control snack. Changes in glucose metabolism will be assessed to determine the potential role of almonds in dietary management of GDM.
- Conditions
- Gestational Diabetes
- Being tested
- Almond Snack Intervention for Gestational Diabetes, Control (placebo) group
- Keywords
- gestational diabetes, pregnancy nutrition, dietary intervention
- Medical subject headings
- Diabetes, Gestational
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Almond Snack Intervention for Gestational DiabetesOther
This intervention involves daily consumption of 43 g of whole almonds, split into two portions (afternoon and evening), for 28 days in pregnant women diagnosed with gestational diabetes who habitually consume evening snacks.
Control (placebo) groupOther
This control involves the daily consumption of a nut-free snack (2 portions) that reflects a 'typical snack' choice among pregnant women with gestational diabetes. It serves as a comparison to assess the specific impact of almond-based evening snacking on overnight glucose regulation.
| Study group | Role | What they receive |
|---|---|---|
| Almond group | Experimental | Participants in the almond group will consume 43 g of almonds daily for 28 days, divided into two equal portions: one in the afternoon and one in the evening. Receives: Other: Almond Snack Intervention for Gestational Diabetes |
| Control group | Placebo comparator | Participants in the control group will consume nut-free snacks (e.g., crackers or savoury biscuits) that are energy-matched to the almond snacks. Receives: Other: Control (placebo) group |
What is being measured
The primary outcome is the main question the study is designed to answer.
Mean nocturnal blood glucose (22.00-07.00h)
Measured: The primary endpoint will be assessed on day 14 and day 28 of the intervention.
Secondary outcomes (23)
Mean daytime glucose 07.00-22.00h
Recommended glucose control target 3.5-7.8mmol/L, AUC <6.7mmol/L, AUC <7.8mmol/L
Measured: Assessed on day 14 and day 28 of the intervention.
Postprandial blood glucose
Mean postprandial blood glucose for 1, 2 \& 4 hours after dinner.
Measured: Assessed on day 14 and day 28 of the intervention.
Glucose variability
Glucose SD, glucose CV
Measured: Assessed on day 14 and 28 of the intervention.
Blood glucose indices
High and low blood glucose indices (HBGI \& LBGI)
Measured: Assessed on day 14 and 28 of the intervention.
HbA1c
Biochemical analysis of maternal blood
Measured: Assessed on day 0 and day 28 of the intervention.
Liver function
Biochemical analysis of maternal blood: gamma-glutamyl transferase (GGT), alanine aminotransferase (ALT), aspartate aminotransferase (AST)
Measured: Assessed on day 0 and day 28 of the intervention.
Maternal metabolome (blood)
Lipid measures, including lipoprotein particles (VLDL subdivided into six subclasses, IDL, LDL subdivided into three subclasses, and HDL subdivided into four subclasses), constituents within each lipoprotein particle type (triglycerides, total cholesterol, free cholesterol and cholesterol ester levels and phospholipid concentrations), fatty acids, amino acids, glycolysis related metabolites, ketone bodies and inflammatory markers.
Measured: Assessed on day 0 and day 28 of the intervention.
Maternal weight in kg
Maternal weight and height will be combined to report BMI in kg/m^2
Measured: Assessed on day 0 and day 28 of the intervention.
Dietary intake using questionnaire
Assessment of dietary intake using Intake24, a validated digital dietary recall system based on the multiple-pass 24-hour recall
Measured: Assessed on or around day 0 (x2), day 14 (x 2) and day 28 (x2) of the intervention.
Assessment of appetite on a Likert scale
Assessment of appetite on a 1-7 Likert scale (i.e., 1 = Not at all hungry, 7 = Extremely hungry)
Measured: Assessed on day 0, day 14, and day 28 of the intervention.
Physical activity using accelerometer
The accelerometer will record physical activity, such as average time spent in moderate, low, and sedentary activity
Measured: Assessed on days 0-28 of the intervention.
Stool
(Optional) may be collected and stored for microbiome analysis
Measured: May be assessed on days 0, 14 and 28 of the intervention.
Sleep quality using accelerometer
The accelerometer will measure sleep quality, such as sleep duration
Measured: Assessed on days 0-28 of the intervention.
Course of GDM
If medication is required for glucose control, such as metformin or insulin (dose, time of initiation)
Measured: Assessed on days 0-28 of the intervention.
Mode of delivery
Measured: Assessed at delivery.
Acceptability of the intervention using questionnaire
A dietary intervention acceptability questionnaire will be used to assess enjoyment, sensory aspects, gastrointestinal effects, palatability, and appetite sensations.
Measured: Assessed on day 28 of the intervention.
Birthweight
Measured: Assessed at delivery.
Neonatal head circumference
Measured: Assessed at delivery.
Neonatal sex
Measured: Assessed at delivery.
Gestational age
Measured: Assessed at delivery.
Neonatal complications
Measured: Assessed at delivery.
Maternal complications
Measured: Assessed at delivery.
Labour onset checklist
Measured: Assessed at delivery.
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted17 Jul 2025
- Study startDec 2026 (estimated)
- Primary completionDec 2027 (estimated)
- Study completionDec 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Gestational DiabetesStudies of the same condition, open and under way.
- More trials run by Guy's and St Thomas' NHS Foundation TrustThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Model description
- Randomised controlled trial
- Masking
- None (open label)
- Enrolment
- 156 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Guy's and St Thomas' NHS Foundation Trust
- Sponsor type
- University, hospital or other
- Collaborators
- King's College London, Almond Board of California
- Responsible party
- Sponsor
- Investigators
- Sara L White, Principal investigator, King's College London
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07069855
- Sponsor's protocol ID
- 325804
- Acronym
- Nutcracker
- Status last verified
- Nov 2025
- First submitted
- 12 May 2025
- Last updated
- 15 Sep 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Undecided
Study at a glance
From the registry record, last updated by the sponsor on 15 Sep 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Nutcracker: Can Almond Nut Consumption Improve Nocturnal Glycaemic Control in Women With Gestational Diabetes Mellitus? A Randomised Controlled Trial
- ClinicalTrials.gov ID
- NCT07069855
- Acronym / sponsor ID
- Nutcracker / 325804
- Conditions
- Gestational Diabetes
- Keywords
- gestational diabetes, pregnancy nutrition, dietary intervention
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 156 participants (estimated)
- Lead sponsor
- Guy's and St Thomas' NHS Foundation TrustUniversity, hospital or other
- Collaborators
- King's College London, Almond Board of California
- Study start
- Dec 2026 (estimated)
- Primary completion
- Dec 2027 (estimated)
- Study completion
- Dec 2027 (estimated)
- First posted
- 17 Jul 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Gestational diabetes, affecting over one in six births globally, is a growing public health concern. Characterised by high blood glucose, it increases the risk of pregnancy complications and raises the mother's long-term risk of type 2 diabetes. Managing high fasting glucose, which reflects elevated overnight levels, is a key challenge. Night-time snacking-more common in women with gestational diabetes-is linked to higher fasting glucose, but the impact of snack quality is unclear. Almonds have been shown to improve glucose control in non-pregnant adults. This study will test whether almonds, as a night-time snack, can improve overnight glucose levels in pregnant women with gestational diabetes. Findings could support a simple, effective dietary strategy to improve outcomes for mothers and babies worldwide.
Detailed description
Gestational diabetes mellitus (GDM) is a significant and increasingly prevalent public health concern, affecting over one-sixth of births globally. A key challenge in its management is fasting hyperglycaemia, which may result from elevated nocturnal glucose concentrations. Nocturnal hyperglycaemia has been linked to an increased risk of large-for-gestational-age infants in women with GDM. These women are also more likely to snack at night, a behaviour associated with higher fasting glucose concentrations; however, the impact of snack quality on overnight glucose regulation remains unclear.
Almond consumption has been shown to improve glycaemia in individuals with prediabetes or type 2 diabetes, potentially through mechanisms such as carbohydrate displacement and the beneficial effects of their nutrient profile, particularly magnesium and monounsaturated fats. Despite this, research in pregnant populations-especially those with GDM-is limited.
This study will investigate whether consuming almonds as an evening snack for four weeks improves overnight glucose regulation in women with GDM. Participants will be randomised to receive either almonds or a nut-free, energy-matched control snack. Changes in glucose metabolism will be assessed to determine the potential role of almonds in dietary management of GDM.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 2
- Model description
- Randomised controlled trial
| Arm | Type | Receives |
|---|---|---|
| Almond group | Experimental | Other: Almond Snack Intervention for Gestational DiabetesParticipants in the almond group will consume 43 g of almonds daily for 28 days, divided into two equal portions: one in the afternoon and one in the evening. |
| Control group | Placebo comparator | Other: Control (placebo) groupParticipants in the control group will consume nut-free snacks (e.g., crackers or savoury biscuits) that are energy-matched to the almond snacks. |
Who may qualify
- Ages
- 16 to 55 years
- Sex
- Female only
- Healthy volunteers
- Not accepted
- Age groups
- Child, Adult
Key inclusion criteria (6 listed)
- Age over 16 years
- Singleton pregnancy
- 25 to 31+6 weeks' gestation diagnosed with GDM using a standard clinical 75g oral glucose tolerance test (OGTT), as per the guidelines of the National Institute of Health and Care Excellence (NICE), and had their first post-diagnosis consultation (approx. 7-10 days later). The NICE criteria state that the diagnosis of GDM will be made with one or more glucose concentrations during the OGTT of >5.6 mmol/l in the fasting state; >7.8 mmol/l 2 hours after 75g glucose
- Planned antenatal care at the same centre
- GDm-Health (a digital app for the management of diabetes in pregnancy) used as part of their management for GDM
Key exclusion criteria (9 listed)
- Age under 16 years or over 55 years
- Multiple pregnancy
- Non-snack consumers
- Smokers
- Women who would work night shifts over the study period
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Almond Snack Intervention for Gestational DiabetesThis intervention involves daily consumption of 43 g of whole almonds, split into two portions (afternoon and evening), for 28 days in pregnant women diagnosed with gestational diabetes who habitually consume evening snacks. | Other | Almond group |
| Control (placebo) groupThis control involves the daily consumption of a nut-free snack (2 portions) that reflects a 'typical snack' choice among pregnant women with gestational diabetes. It serves as a comparison to assess the specific impact of almond-based evening snacking on overnight glucose regulation. | Other | Control group |
Primary outcome
Mean nocturnal blood glucose (22.00-07.00h)
Time frame: The primary endpoint will be assessed on day 14 and day 28 of the intervention.
23 secondary outcomes
Mean daytime glucose 07.00-22.00h
Time frame: Assessed on day 14 and day 28 of the intervention.
Postprandial blood glucose
Time frame: Assessed on day 14 and day 28 of the intervention.
Glucose variability
Time frame: Assessed on day 14 and 28 of the intervention.
Blood glucose indices
Time frame: Assessed on day 14 and 28 of the intervention.
HbA1c
Time frame: Assessed on day 0 and day 28 of the intervention.
Liver function
Time frame: Assessed on day 0 and day 28 of the intervention.
Maternal metabolome (blood)
Time frame: Assessed on day 0 and day 28 of the intervention.
Maternal weight in kg
Time frame: Assessed on day 0 and day 28 of the intervention.
Dietary intake using questionnaire
Time frame: Assessed on or around day 0 (x2), day 14 (x 2) and day 28 (x2) of the intervention.
Assessment of appetite on a Likert scale
Time frame: Assessed on day 0, day 14, and day 28 of the intervention.
Physical activity using accelerometer
Time frame: Assessed on days 0-28 of the intervention.
Stool
Time frame: May be assessed on days 0, 14 and 28 of the intervention.
Sleep quality using accelerometer
Time frame: Assessed on days 0-28 of the intervention.
Course of GDM
Time frame: Assessed on days 0-28 of the intervention.
Mode of delivery
Time frame: Assessed at delivery.
Acceptability of the intervention using questionnaire
Time frame: Assessed on day 28 of the intervention.
Birthweight
Time frame: Assessed at delivery.
Neonatal head circumference
Time frame: Assessed at delivery.
Neonatal sex
Time frame: Assessed at delivery.
Gestational age
Time frame: Assessed at delivery.
Neonatal complications
Time frame: Assessed at delivery.
Maternal complications
Time frame: Assessed at delivery.
Labour onset checklist
Time frame: Assessed at delivery.
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 15 Sep 2026.
- Individual participant dataSharing planned: Undecided
Related trials for Gestational Diabetes
RecruitingEarly Phase 1
Role of ET-1, Physical Activity, and Sedentary Behavior in Microvascular Dysfunction Following GDM
Gestational Diabetes, Endothelial Dysfunction
RecruitingEarly Phase 1
Metformin for the Treatment of Microvascular Dysfunction After Gestational Diabetes
Gestational Diabetes
Recruiting
Fueling Labor: Protein Supplementation for Intrapartum Glucose Control
Diabetes During Pregnancy
Not yet recruiting
Usability Evaluation of Gen AI-based Nutrition Chatbot for Pregnant Women
Diabetes, Gestational, Pre-eclampsia
Not yet recruiting
A Randomized Trial to Reduce Blood Pressure at One Year Postpartum After Preeclampsia
Adverse Pregnancy Outcomes, Cardiovascular Diseases
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Olivia Righton contact
Sara L White principal investigator
King's College London
Questions about this trial
What is this clinical trial studying?
A study testing Almond Snack Intervention for Gestational Diabetes in people with Gestational Diabetes, run by Guy's and St Thomas' NHS Foundation Trust.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 6 inclusion and 9 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: opening soon, as of the sponsor's last update on 15 Sep 2026. Status can change between updates, so confirm with the study contact before making plans.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Sara L White (+44 (0) 20 7188 8151, sara.white@kcl.ac.uk), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Mean nocturnal blood glucose (22.00-07.00h) (time frame: The primary endpoint will be assessed on day 14 and day 28 of the intervention.). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 15 Sep 2026.