ClinicalTrials.gg
RecruitingNCT07603739NUTSUpdated Jul 17, 2026

Eating Almonds Before a Meal to Control Blood Sugar

An interventional study of Premeal almond ingestion in Glucose Control, Prediabetes (Insulin Resistance, Impaired Glucose Tolerance) and Precision Medicine, sponsored by Pennington Biomedical Research Center. Recruiting at 1 site in United States. Open to participants aged 25 Years to 50 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-07-17.

Sponsored by Pennington Biomedical Research Center · Not applicable, Interventional, and Basic science

From the registry’s dates

  • Started Jun 2026; still recruiting 4 months later.
Phase
Not applicable
Study type
Interventional
Enrollment
25
Allocation
Randomized
Ages
25 Years to 50 Years
Sex
All
01

Study summary

The goal of this study is to learn whether eating a small serving of almonds before meals can improve blood sugar control in adults who have early signs of problems with blood sugar regulation. The main questions it aims to answer are:

  1. Does eating almonds before a meal reduce the rise in blood sugar after eating?
  2. Do some people consistently benefit more than others from eating almonds before meals?
Read the detailed description

Large rises in blood sugar after eating are an early warning sign of type 2 diabetes, and simple dietary strategies may help lower this risk. This study aims to understand whether eating a small serving of almonds before meals can help reduce postprandial blood sugar levels in adults who are at increased risk for developing type 2 diabetes. Participants will take part in two phases of the study: one conducted in a research clinic to carefully measure short-term blood sugar responses, and another conducted while participants follow a provided diet at home over a longer period. Sometimes participants will eat almonds before meals, and sometimes they will not. The study hypothesis is that eating almonds before meals will lower blood sugar rises after eating, and that some people will benefit more than others in a consistent way that can be observed both in the clinic and during everyday living.

02

Conditions studied

  • Glucose Control
  • Prediabetes (Insulin Resistance, Impaired Glucose Tolerance)
  • Precision Medicine
  • Nutrition

Keywords

  • Nutrition
  • Precision Medicine
  • Precision Nutrition
  • Glucose Control
  • Impaired Glucose Tolerance
  • Insulin Resistance
  • Prediabetes
03

In context

Prediabetic State

918 studies on the registry are indexed under Prediabetic State; 232 are open to participants now.

This study's planned enrollment of 25 is below the median of 62 across 762 interventional studies indexed under Prediabetic State.

Browse Prediabetic State studies →

Lead sponsor

Pennington Biomedical Research Center is the lead sponsor of 284 studies on the registry; 31 are open to participants now.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
25 Years to 50 Years
Sexes eligible
All
Accepts healthy volunteers
Yes

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

  • Adults aged 25-50 years
  • Females over 40 years must have had a cycle in the last 6 months
  • (BMI) at least 18.5 and at most 55.0 kg/m2
  • Impaired blood glucose by at least one of the following criteria:
  • Fasting blood glucose at least 100 mg/dL (5.6 mmol/L) and less than 125 mg/dL (6.9 mmol/L)
  • at least 5.7% and less than 6.5%
  • Willing and able to comply with study foods
  • Willing and able to ingest acetaminophen as part of study procedures
  • Able to read, speak, and understand English

Exclusion criteria

Exclusion Criteria:

  • Weight change ≥5% in past 6 months, actively trying to lose weight, or unwilling to remain weight stable throughout the study based on self-report
  • Recent history within past 12 months of medical provider-diagnosed cardiovascular, renal, or liver disease that required treatment
  • Current or past diagnosis of cancer (except skin cancer) in the last 5 years
  • Current or past diagnosis of type 1 or type 2 diabetes
  • Recent history within past 12 months of medical provider-diagnosed gastrointestinal or neurological disorders if not managed/stable for at least 3 months (with or without treatment)
  • Recent history within past 12 months of medical provider-diagnosed psychiatric disorders including eating disorders or severe depression if not managed/stable for at least 3 months (with or without treatment)
  • Food allergies or other reasons preventing consumption of study foods
  • Any glucose-lowering medication except biguanides (e.g., Metformin) if stable for at least 3 months or incretins (i.e., GLP-1RA-based) if stable for at least 3 months
  • Current smoking or vaping or history of smoking or vaping in the past 6 months
  • Binge and/or heavy drinking (i.e., >3 drinks on any given occasion and/or >7 drinks/week)
  • Currently pregnant or planning to become pregnant or breastfeed in the next 3 months by self-report
Terms in these criteria, in plain language(2)

Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.

BMI (body mass index)

Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.

What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.

HbA1c

A blood test of average blood sugar over the past two to three months, given as a percentage or in mmol/mol. 6.5% (48 mmol/mol) or more is the usual threshold for diabetes, normally confirmed by a second test.

05

Study design

Phase
Not applicable
Primary purpose
Basic science
Allocation
Randomized
Intervention model
Crossover assignment
Masking
Double (Investigator, Outcomes assessor)
Enrollment
25 participants (estimated)

Study arms

  • Experimental
    Randomization Sequence 1

    One of the randomization sequences. Phase 1: MMTT+, MMTT-, MMTT+, MMTT- \| Phase 2: SAD+, SAD-. In Phase 1, MMTT+ refers to a mixed meal tolerance test with premeal almond ingestion (active condition). MMTT- refers to a mixed meal tolerance test without premeal almond ingestion (control condition). In Phase 2, SAD+ refers to the 10-day controlled feeding diet period using a Standard American Diet with thrice daily premeal almond ingestion (active condition). SAD- refers to the 10-day controlled feeding diet period using a Standard American Diet without premeal almond ingestion (control condition).

    Dietary Supplement: Premeal almond ingestion

  • Experimental
    Randomization Sequence 2

    One of the randomization sequences. Phase 1: MMTT-, MMTT+, MMTT-, MMTT+ \| Phase 2: SAD+, SAD-. In Phase 1, MMTT+ refers to a mixed meal tolerance test with premeal almond ingestion (active condition). MMTT- refers to a mixed meal tolerance test without premeal almond ingestion (control condition). In Phase 2, SAD+ refers to the 10-day controlled feeding diet period using a Standard American Diet with thrice daily premeal almond ingestion (active condition). SAD- refers to the 10-day controlled feeding diet period using a Standard American Diet without premeal almond ingestion (control condition).

    Dietary Supplement: Premeal almond ingestion

  • Experimental
    Randomization Sequence 3

    One of the randomization sequences. Phase 1: MMTT+, MMTT-, MMTT-, MMTT+ \| Phase 2: SAD+, SAD-. In Phase 1, MMTT+ refers to a mixed meal tolerance test with premeal almond ingestion (active condition). MMTT- refers to a mixed meal tolerance test without premeal almond ingestion (control condition). In Phase 2, SAD+ refers to the 10-day controlled feeding diet period using a Standard American Diet with thrice daily premeal almond ingestion (active condition). SAD- refers to the 10-day controlled feeding diet period using a Standard American Diet without premeal almond ingestion (control condition).

    Dietary Supplement: Premeal almond ingestion

  • Experimental
    Randomization Sequence 4

    One of the randomization sequences. Phase 1: MMTT-, MMTT+, MMTT+, MMTT- \| Phase 2: SAD+, SAD-. In Phase 1, MMTT+ refers to a mixed meal tolerance test with premeal almond ingestion (active condition). MMTT- refers to a mixed meal tolerance test without premeal almond ingestion (control condition). In Phase 2, SAD+ refers to the 10-day controlled feeding diet period using a Standard American Diet with thrice daily premeal almond ingestion (active condition). SAD- refers to the 10-day controlled feeding diet period using a Standard American Diet without premeal almond ingestion (control condition).

    Dietary Supplement: Premeal almond ingestion

  • Experimental
    Randomization Sequence 5

    One of the randomization sequences. Phase 1: MMTT+, MMTT-, MMTT+, MMTT- \| Phase 2: SAD-, SAD+. In Phase 1, MMTT+ refers to a mixed meal tolerance test with premeal almond ingestion (active condition). MMTT- refers to a mixed meal tolerance test without premeal almond ingestion (control condition). In Phase 2, SAD+ refers to the 10-day controlled feeding diet period using a Standard American Diet with thrice daily premeal almond ingestion (active condition). SAD- refers to the 10-day controlled feeding diet period using a Standard American Diet without premeal almond ingestion (control condition).

    Dietary Supplement: Premeal almond ingestion

  • Experimental
    Randomization Sequence 6

    One of the randomization sequences. Phase 1: MMTT-, MMTT+, MMTT-, MMTT+ \| Phase 2: SAD-, SAD+. In Phase 1, MMTT+ refers to a mixed meal tolerance test with premeal almond ingestion (active condition). MMTT- refers to a mixed meal tolerance test without premeal almond ingestion (control condition). In Phase 2, SAD+ refers to the 10-day controlled feeding diet period using a Standard American Diet with thrice daily premeal almond ingestion (active condition). SAD- refers to the 10-day controlled feeding diet period using a Standard American Diet without premeal almond ingestion (control condition).

    Dietary Supplement: Premeal almond ingestion

  • Experimental
    Randomization Sequence 7

    One of the randomization sequences. Phase 1: MMTT+, MMTT-, MMTT-, MMTT+ \| Phase 2: SAD-, SAD+. In Phase 1, MMTT+ refers to a mixed meal tolerance test with premeal almond ingestion (active condition). MMTT- refers to a mixed meal tolerance test without premeal almond ingestion (control condition). In Phase 2, SAD+ refers to the 10-day controlled feeding diet period using a Standard American Diet with thrice daily premeal almond ingestion (active condition). SAD- refers to the 10-day controlled feeding diet period using a Standard American Diet without premeal almond ingestion (control condition).

    Dietary Supplement: Premeal almond ingestion

  • Experimental
    Randomization Sequence 8

    One of the randomization sequences. Phase 1: MMTT-, MMTT+, MMTT+, MMTT-, \| Phase 2: SAD-, SAD+. In Phase 1, MMTT+ refers to a mixed meal tolerance test with premeal almond ingestion (active condition). MMTT- refers to a mixed meal tolerance test without premeal almond ingestion (control condition). In Phase 2, SAD+ refers to the 10-day controlled feeding diet period using a Standard American Diet with thrice daily premeal almond ingestion (active condition). SAD- refers to the 10-day controlled feeding diet period using a Standard American Diet without premeal almond ingestion (control condition).

    Dietary Supplement: Premeal almond ingestion

Interventions

  • Dietary supplementPremeal almond ingestion

    Premeal almond ingestion (18 g; \~100 kcal) 30 minutes prior to meal

06

What researchers measure

Primary outcomes

  1. Postprandial glucose assessed during acute meal test

    The primary endpoint will be the difference in plasma glucose incremental area under the curve (iAUC) assessed via intravenous blood sampling over three hours following a standardized mixed meal tolerance test (MMTT) with premeal ingestion of 18 g of almonds 30 minutes prior (MMTT+) compared to without (MMTT-). This effect will be averaged across the replicated acute challenge visits in the repeated crossover design.

    Time frame: Days 1-4: -35 minutes, -5 minutes, 15 minutes, 30 minutes, 60 minutes, 90 minutes, 120 minutes, 180 minutes relative to ingestion of premeal almonds at -30 minutes (if applicable) and the mixed meal tolerance test at 0 minutes.

Secondary outcomes

  1. Interindividual variability in the postprandial glucose assessed during acute meal test

    Variability in response to the single-dose, acute premeal almond supplementation prior to the MMTT will be characterized according to previously established procedures using Pearson's correlation between the first and second replicate of the control-adjusted treatment effect (i.e., MMTT+ vs MMTT-). That is, the correlation between the difference in iAUC during the first crossover trial (i.e., iAUC during MMTT+ minus iAUC during MMTT-) and the difference in iAUC during the second crossover trial (i.e., iAUC during MMTT+ minus iAUC during MMTT-).

    Time frame: Days 1-4: -35 minutes, -5 minutes, 15 minutes, 30 minutes, 60 minutes, 90 minutes, 120 minutes, 180 minutes relative to ingestion of premeal almonds at -30 minutes (if applicable) and the mixed meal tolerance test at 0 minutes.

  2. Consistency between acute glycemic response and longer-term glycemic control

    Whether the individual glucose-lowering effect of the almond preload observed during the acute, repeated crossover, controlled in-laboratory MMTT predicts an individual's glycemic control during the 10-day, free-living, controlled-feeding phase in which almonds will be consumed thrice daily prior to each main meal on the background of a Standard American diet. We will evaluate this via the regression coefficient derived from a linear regression with the magnitude of the acute treatment effect in Days 1-4 (i.e., the difference in iAUC between MMTT+ and MMTT- averaged between both crossover trials) as the predictor and the magnitude of the treatment effect in Days 5-25 (i.e., the difference in average iAUC across the 10-day controlled feeding diet periods between MMTT+ and MMTT-) as the outcome.

    Time frame: Days 1-4: Days 1-4: -35 minutes, -5 minutes, 15 minutes, 30 minutes, 60 minutes, 90 minutes, 120 minutes, 180 minutes relative to ingestion of premeal almonds at -30 minutes (if applicable) and the mixed meal tolerance test at 0 minutes. Days 5-25

Other outcomes

  1. Acute postprandial glucose

    The difference in plasma glucose assessed via intravenous blood sampling over three hours following a standardized mixed meal tolerance test (MMTT) with premeal ingestion of 18 g of almonds 30 minutes prior (MMTT+) compared to without (MMTT-). This effect will be averaged across the replicated acute challenge visits in the repeated crossover design.

    Time frame: Days 1-4: -35 minutes, -5 minutes, 15 minutes, 30 minutes, 60 minutes, 90 minutes, 120 minutes, 180 minutes relative to ingestion of premeal almonds at -30 minutes (if applicable) and the mixed meal tolerance test at 0 minutes.

  2. Acute postprandial gastric emptying

    The difference in acetaminophen appearance (gastric emptying) assessed via intravenous blood sampling over three hours following a standardized mixed meal tolerance test (MMTT) with premeal ingestion of 18 g of almonds 30 minutes prior (MMTT+) compared to without (MMTT-). This effect will be averaged across the replicated acute challenge visits in the repeated crossover design.

    Time frame: Days 1-4: -35 minutes, -5 minutes, 15 minutes, 30 minutes, 60 minutes, 90 minutes, 120 minutes, 180 minutes relative to ingestion of premeal almonds at -30 minutes (if applicable) and the mixed meal tolerance test at 0 minutes.

  3. Acute postprandial insulin

    The difference in plasma insulin assessed via intravenous blood sampling over three hours following a standardized mixed meal tolerance test (MMTT) with premeal ingestion of 18 g of almonds 30 minutes prior (MMTT+) compared to without (MMTT-). This effect will be averaged across the replicated acute challenge visits in the repeated crossover design.

    Time frame: Days 1-4: -35 minutes, -5 minutes, 15 minutes, 30 minutes, 60 minutes, 90 minutes, 120 minutes, 180 minutes relative to ingestion of premeal almonds at -30 minutes (if applicable) and the mixed meal tolerance test at 0 minutes.

  4. Acute postprandial glucagon-like peptide 1

    The difference in plasma glucagon-like peptide 1 assessed via intravenous blood sampling over three hours following a standardized mixed meal tolerance test (MMTT) with premeal ingestion of 18 g of almonds 30 minutes prior (MMTT+) compared to without (MMTT-). This effect will be averaged across the replicated acute challenge visits in the repeated crossover design.

    Time frame: Days 1-4: -35 minutes, -5 minutes, 15 minutes, 30 minutes, 60 minutes, 90 minutes, 120 minutes, 180 minutes relative to ingestion of premeal almonds at -30 minutes (if applicable) and the mixed meal tolerance test at 0 minutes.

  5. Cardiometabolic health - fasting glucose

    The difference in the change of fasting plasma blood glucose from before to after a 10-day controlled feeding diet period with thrice daily premeal ingestion of 18 g of almonds 30 minutes to each meal (MMTT+) compared to without (MMTT-).

    Time frame: Days 5-25

  6. Cardiometabolic health - fasting high-density lipoprotein cholesterol

    The difference in the change of fasting high-density lipoprotein cholesterol from before to after a 10-day controlled feeding diet period with thrice daily premeal ingestion of 18 g of almonds 30 minutes to each meal (MMTT+) compared to without (MMTT-).

    Time frame: Days 5-25

  7. Cardiometabolic health - fasting low-density lipoprotein cholesterol

    The difference in the change of fasting low-density lipoprotein cholesterol from before to after a 10-day controlled feeding diet period with thrice daily premeal ingestion of 18 g of almonds 30 minutes to each meal (MMTT+) compared to without (MMTT-).

    Time frame: Days 5-25

  8. Cardiometabolic health - fasting total cholesterol

    The difference in the change of fasting total cholesterol from before to after a 10-day controlled feeding diet period with thrice daily premeal ingestion of 18 g of almonds 30 minutes to each meal (MMTT+) compared to without (MMTT-).

    Time frame: Days 5-25

  9. Cardiometabolic health - fasting insulin

    The difference in the change of fasting plasma insulin from before to after a 10-day controlled feeding diet period with thrice daily premeal ingestion of 18 g of almonds 30 minutes to each meal (MMTT+) compared to without (MMTT-).

    Time frame: Days 5-25

  10. Cardiometabolic health - fasting glucagon-like peptide 1

    The difference in the change of fasting glucagon-like peptide 1 from before to after a 10-day controlled feeding diet period with thrice daily premeal ingestion of 18 g of almonds 30 minutes to each meal (MMTT+) compared to without (MMTT-).

    Time frame: Days 5-25

  11. Cardiometabolic health - fasting C-reactive protein

    The difference in the change of fasting C-reactive protein from before to after a 10-day controlled feeding diet period with thrice daily premeal ingestion of 18 g of almonds 30 minutes to each meal (MMTT+) compared to without (MMTT-).

    Time frame: Days 5-25

  12. Cardiometabolic health - 24-hour glucose

    The difference in average 24-hour glucose assessed via CGM during a 10-day controlled feeding diet period with thrice daily premeal ingestion of 18 g of almonds 30 minutes to each meal (MMTT+) compared to without (MMTT-).

    Time frame: Days 5-25

  13. Cardiometabolic health - glucose incremental area under the curve

    The difference in average meal blood glucose incremental area under the curve (iAUC) assessed via CGM during a 10-day controlled feeding diet period with thrice daily premeal ingestion of 18 g of almonds 30 minutes to each meal (MMTT+) compared to without (MMTT-).

    Time frame: Days 5-25

  14. Cardiometabolic health - glucose area under the curve

    The difference in average meal blood glucose area under the curve (AUC) assessed via CGM during a 10-day controlled feeding diet period with thrice daily premeal ingestion of 18 g of almonds 30 minutes to each meal (MMTT+) compared to without (MMTT-).

    Time frame: Days 5-25

  15. Cardiometabolic health - glucose standard deviation

    The difference in average blood glucose standard deviation (SD) assessed via CGM during a 10-day controlled feeding diet period with thrice daily premeal ingestion of 18 g of almonds 30 minutes to each meal (MMTT+) compared to without (MMTT-).

    Time frame: Days 5-25

  16. Cardiometabolic health - glucose coefficient of variation

    The difference in average blood glucose coefficient of variation (CV) assessed via CGM during a 10-day controlled feeding diet period with thrice daily premeal ingestion of 18 g of almonds 30 minutes to each meal (MMTT+) compared to without (MMTT-).

    Time frame: Days 5-25

  17. Cardiometabolic health - glucose time in range

    The difference in average glucose time in range assessed via CGM during a 10-day controlled feeding diet period with thrice daily premeal ingestion of 18 g of almonds 30 minutes to each meal (MMTT+) compared to without (MMTT-).

    Time frame: Days 5-25

07

Study locations

1 of 1 sites recruiting
  • Pennington Biomedical Research Center
    Baton Rouge, Louisiana 70808, United States
    Recruiting
08

References and documents

Individual participant data

Plan to share: No — Data will be shared upon reasonable request to the study investigator and upon successful execution of a data transfer/sharing agreement.

No publications or documents are linked to this record.

09

Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Jul 17, 2026, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT07603739
Responsible party
Kaja Falkenhain (Postdoctoral Fellow, Pennington Biomedical Research Center) — Principal investigator
First posted
May 22, 2026
Start date
Jun 23, 2026
Primary completion
Mar 2028 (estimated)
Completion
Jul 2028 (estimated)
Last update
Jul 17, 2026

Study contacts

Kaja Falkenhain, PhD
Contact
kaja.falkenhain@pbrc.edu
225-763-2558

Oversight

Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

Interested in this study?

Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.

Contact study team

Follow this study

Get an email when the registry record changes — status, dates, results — or when someone posts here.

Sign in to follow

Discussion

Questions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.

Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.

Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.

Start the discussion