An observational study in Hypoglycemia, sponsored by Joslin Diabetes Center. Active, not recruiting at 1 site in United States. Open to participants aged 18 Years to 65 Years. Per ClinicalTrials.gov, last updated 2026-02-06.
Sponsored by Joslin Diabetes Center · Observational
This study is designed to evaluate individuals who are currently experiencing symptoms of hypoglycemia, in order to discern correlations between microbiome composition and patterns of postprandial glycemia.
Recent studies have shown that analysis of the gastrointestinal microbiome can be used to predict glycemic response to dietary intake. Specifically, integrative analysis of dietary consumption, anthropometrics, physical activity and gut microbiota composition can be used to predict postprandial glycemic excursions. The investigators hypothesize that individualized assessment of glycemic responses to food, together with analysis of the gut microbiome, will allow the design of a personalized dietary approach to minimize glycemic excursions for patients with post-bariatric and other forms of largely postprandial hypoglycemia. Identification of factors predictive of glycemic excursions and subsequent hypoglycemia may ultimately allow individuals to tailor their diet towards foods which would not induce hypersecretion of insulin and subsequent hypoglycemia.
706 studies on the registry are indexed under Hypoglycemia; 94 are open to participants now.
This study's planned enrollment of 28 is below the median of 86 across 131 observational studies indexed under Hypoglycemia.
Browse Hypoglycemia studies →Joslin Diabetes Center is the lead sponsor of 80 studies on the registry; 7 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Patients who experience hypoglycemia after bariatric or other upper gastrointestinal surgery or those with reactive hypoglycemia in the absence of surgery.
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.
Exclusion Criteria
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.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.
Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.
The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.
“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.
A yellow substance made when red blood cells are broken down, which the liver clears. A high level can mean a problem with the liver or the bile ducts.
Criteria often allow more for people with Gilbert’s syndrome, a harmless inherited condition that raises bilirubin.
The New York Heart Association’s four classes of how much heart failure limits physical activity.
Studies set their own limit — many outside heart failure leave out class III–IV, while heart failure studies may ask for a particular class. Check the class this study names.
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ALT and AST (liver enzymes)
Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.
Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ULN (upper limit of normal)
The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.
“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Bilirubin
A yellow substance made when red blood cells are broken down, which the liver clears. A high level can mean a problem with the liver or the bile ducts.
Criteria often allow more for people with Gilbert’s syndrome, a harmless inherited condition that raises bilirubin.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
NYHA class (heart failure)
The New York Heart Association’s four classes of how much heart failure limits physical activity.
Studies set their own limit — many outside heart failure leave out class III–IV, while heart failure studies may ask for a particular class. Check the class this study names.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Cancer (malignancy)
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Platelets
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Corticosteroids (steroids)
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Childbearing potential
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants will wear a Dexcom continuous glucose monitor (CGM) and activity monitor for two weeks. They will not be aware of sensor glucose values. A stool sample will be collected. The investigators will evaluate relationships between patterns of postprandial glycemia, recorded by CGM, food intake, and microbiome composition.
Analysis of cumulative duration of hypoglycemia
Duration of hypoglycemia will be assessed by: (1) the number of minutes per day with hypoglycemia, defined as sensor glucose \<70 mg/dl, and (2) the number of minutes per day of severe hypoglycemia, defined as sensor glucose \<55 mg/dl. Data will be captured for the entire 24 hour period as well as day and night subsets.
Time frame: 2 weeks
Analysis of frequency of glycemic excursions
Hypoglycemia frequency will be assessed by: (1) number of episodes of hypoglycemia, both moderate (55-70 mg/dl) and severe (\<55 mg/dl), (2) number of episodes requiring assistance, and (4) number of episodes of hyperglycemia (\>180 mg/dl). All data will be averaged and reported as episodes per day.
Time frame: 2 weeks
Impact of activity on glycemic patterns in post-bariatric hypoglycemia
Activity measures (total step number per day) will be analyzed to determine relationship to changes in sensor glucose levels. Data will be integrated to determine relationships between glycemic patterns, diet, and microbiome.
Time frame: 2 weeks
Impact of diet on glycemic patterns in post-bariatric hypoglycemia
Dietary information will be transcribed and recorded from participants' food diaries. Data will be integrated to determine relationships between glycemic patterns, diet, and microbiome.
Time frame: 2 weeks
Analysis of microbiome in individuals with post-bariatric hypoglycemia
Stool samples will be analyzed to determine microbiome community by 18S sequencing. Data will be integrated to determine relationships between glycemic patterns, diet, and microbiome.
Time frame: 2 weeks
Plan to share: No
This study is active, not recruiting, as verified in Feb 2026. You cannot join it, but the record below documents what was studied.
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Joslin Diabetes Center