Fructose Intake for Healthy Subjects

Overseen By Mark Herman, MD

Age: 18 - 65

Sex: Any

Trial Phase: Academic

Sponsor: Baylor College of Medicine

Must not be taking: Any medications

Disqualifiers: Significant illness, Fructose intolerance, Pregnancy, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: 3

Duration: 2 weeks

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial aims to discover how consuming fructose affects certain metabolic markers in the blood, such as the soluble leptin receptor, compared to glucose. Participants will help researchers understand the different metabolic effects of these sugars by drinking a fructose or glucose beverage and undergoing blood tests. It is ideal for healthy adults aged 18-64 with a BMI of 19 to 30, who do not have significant medical conditions. As an unphased trial, this study offers participants the opportunity to contribute to foundational research that could shape future dietary guidelines.

Will I have to stop taking my current medications?

Yes, you will need to stop taking any medications except oral contraceptives to participate in this trial.

Is there any evidence suggesting that this trial's treatments are likely to be safe?

Research has shown that consuming moderate amounts of fructose for two weeks does not harm how the body handles sugar in healthy people, meaning it doesn't negatively affect insulin sensitivity. However, high fructose intake is linked to health problems like obesity and fatty liver disease, typically occurring with excessive consumption, not the moderate amounts used in this study.

Glucose is generally safe when consumed in moderation and often treats low blood sugar. Excessive glucose can cause health problems, especially for people with diabetes, but this is unlikely with the controlled amounts in this study.

Both fructose and glucose are present in many foods, and research indicates they are well-tolerated in moderate amounts by healthy adults. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Researchers are excited about this trial because it explores how the body metabolizes fructose versus glucose. Unlike many studies that focus on disease treatment, this trial aims to understand the metabolic impact of these sugars in healthy individuals. By comparing how the body processes these sugars, researchers hope to uncover insights that could inform dietary guidelines and influence nutritional recommendations. This could eventually lead to more personalized nutrition strategies for maintaining health and preventing metabolic diseases.

What evidence suggests that this trial's treatments could be effective?

This trial will compare the effects of fructose and glucose ingestion on metabolism. Research has shown that fructose can affect metabolism more negatively than glucose. Studies have linked excessive fructose consumption to obesity, metabolic syndrome (a group of conditions that increase the risk of heart disease and diabetes), and other health problems. Fructose can impact the connection between the gut and liver, possibly leading to worse metabolic health. In contrast, glucose typically causes blood sugar levels to rise quickly, a normal bodily reaction. However, glucose's effect can vary depending on its form and a person's overall diet. These differences in how the body responds to fructose and glucose motivate scientists to compare them in this trial. Participants will start with either fructose or glucose and switch after two weeks, allowing for a direct comparison of metabolic responses. ^{1 6 7 8 9}

Are You a Good Fit for This Trial?

This trial is for healthy adults aged 18-64 with a BMI of 19-30 kg/m². Participants must be willing to fast, consume beverages with fructose or glucose, and have their blood drawn regularly during two separate visits.

Inclusion Criteria

BMI: Participants must have a Body Mass Index (BMI) between 19 and 30 kg/m² (healthy weight to slightly overweight)

I am a healthy volunteer without significant medical conditions.

I am either male or female.

Exclusion Criteria

Known significant medical illness

History of fructose intolerance

Pregnancy

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

1 week

1 visit (phone call)

Treatment

Participants consume a beverage containing either 75g of fructose or glucose and have blood drawn at regular intervals for up to 5 hours

2 weeks

2 visits (in-person)

Follow-up

Participants are monitored for changes in metabolic markers after treatment

4 weeks

What Are the Treatments Tested in This Trial?

Interventions

• Fructose Ingestion
• Glucose Ingestion

Trial Overview

The study compares the metabolic effects of fructose versus glucose ingestion in healthy individuals. It focuses on how these sugars influence circulating metabolic markers like the soluble leptin receptor after consumption.

How Is the Trial Designed?

Group I: Glucose First, Fructose Second (10 participants) Experimental Treatment 2 Interventions

Participants will first consume 75g of glucose in 225ml of water, followed by the same blood sampling schedule. After 2 weeks, they will switch to 75g of fructose, with blood samples taken at the same intervals.

Group II: Fructose First, Glucose Second (10 participants) Experimental Treatment 2 Interventions

Participants will first consume 75g of fructose in 225ml of water. Blood samples will be taken at specific intervals to measure metabolic responses. After 2 weeks, they will consume 75g of glucose in 225ml of water, with blood samples taken at the same intervals.

Who Is Running the Clinical Trial?

Baylor College of Medicine

Lead Sponsor

Trials

1,044

Recruited

6,031,000+

Published Research Related to This Trial

In a study involving 24 participants with type 2 diabetes, allulose significantly reduced postprandial blood glucose levels by 8% at a dose of 10 g compared to a control, indicating its potential as a beneficial sweetener for blood sugar management.

Fructose did not show any effect on blood glucose levels at any dose, highlighting that allulose may be a more effective option for individuals with type 2 diabetes in regulating post-meal glucose spikes.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The effect of small doses of fructose and allulose on postprandial glucose metabolism in type 2 diabetes: A double-blind, randomized, controlled, acute feeding, equivalence trial. Noronha, JC., Braunstein, CR., Glenn, AJ., et al.[2023]

The study suggests that the differences in how fructose and glucose affect food intake are influenced more by factors like timing and volume of consumption rather than inherent differences in their ability to induce feelings of fullness.

Overall, there is insufficient evidence to support the idea that fructose or high-fructose corn syrup is less satiating than glucose or sucrose, indicating that their roles in the obesity epidemic may not be as straightforward as previously thought.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Fructose and satiety. Moran, TH.[2023]

In a study involving 10 healthy adults, fructose absorption varied significantly, with some individuals able to absorb over 50 g, while one subject showed malabsorption at just 10 g, indicating a wide range of individual responses to fructose.

The presence of glucose alongside fructose improved absorption, suggesting that glucose enhances fructose uptake, and highlighting the potential for different intestinal transport mechanisms for fructose.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Absorption capacity of fructose in healthy adults. Comparison with sucrose and its constituent monosaccharides. Rumessen, JJ., Gudmand-Høyer, E.[2022]

Small doses of fructose (≤10 g/meal) and tagatose have been shown to significantly reduce HbA1c and fasting glucose levels in individuals with and without diabetes, suggesting potential long-term benefits for glycemic control.

The evidence for the effectiveness of tagatose is considered moderate, while the evidence for fructose and allulose is graded as low, indicating a need for more long-term studies to confirm these findings.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The Effect of Small Doses of Fructose and Its Epimers on Glycemic Control: A Systematic Review and Meta-Analysis of Controlled Feeding Trials. Noronha, JC., Braunstein, CR., Blanco Mejia, S., et al.[2022]

Dietary fructose significantly increases fasting triglycerides and LDL cholesterol levels compared to glucose, which does not have these effects, highlighting the different metabolic impacts of these sugars over a 4- to 6-week period.

In free-living conditions, adding moderate amounts of fructose to the diet (30-60 g) did not significantly affect lipid or glucose biomarkers, suggesting that the context of sugar intake matters for metabolic health.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Dietary fructose and glucose differentially affect lipid and glucose homeostasis. Schaefer, EJ., Gleason, JA., Dansinger, ML.[2023]

In a study involving healthy subjects, cellobiose was found to be safe and well-tolerated, with a maximum tolerated dose identified as 20 g for single use and 15 g twice daily for repeated consumption.

Despite some mild gastrointestinal side effects like flatulence and transient diarrhea in sensitive individuals, the overall tolerability rating was high, indicating that cellobiose could be a beneficial low-caloric bulking agent in food products.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

A Dose-Escalation Study Demonstrates the Safety and Tolerability of Cellobiose in Healthy Subjects. Moré, MI., Postrach, E., Bothe, G., et al.[2020]

Adult rats can effectively absorb small amounts of fructose (0.4 g), but higher doses (greater than 0.6 g) lead to acute malabsorption, indicating a threshold for effective absorption.

The presence of glucose or galactose significantly enhances fructose absorption, especially when consumed together in equal amounts, while sucrose and certain inhibitors can reduce this absorption.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Intestinal absorption of fructose in the rat. Fujisawa, T., Riby, J., Kretchmer, N.[2019]

A 90-day toxicity test on rats showed that D-allulose, produced from a non-GMO source, has a No Observed Adverse Effect Level (NOAEL) of 5,000 mg/kg/day, indicating it is safe for consumption at this level.

The study found only minor changes in health indicators at high doses, supporting the classification of D-allulose as a safe and ordinary substitute for sucrose with 70% of its sweetness and ultra-low energy.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

90-Day repeated oral toxicity test of D-allulose produced from Microbacterium foliorum. An, M., Lee, J., Park, YC., et al.[2020]

Recent randomized controlled trials (RCTs) indicate that consuming fructose, high fructose corn syrup (HFCS), and sucrose at normal dietary levels does not show significant adverse health effects, challenging common concerns about these sugars.

The review emphasizes the need for caution in making health claims about these sugars, as most studies have compared pure forms of sugars rather than how they are typically consumed in diets.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The metabolic and endocrine response and health implications of consuming sugar-sweetened beverages: findings from recent randomized controlled trials. Rippe, JM.[2023]

D-psicose is rapidly absorbed into the bloodstream after oral administration, reaching peak concentration within 1 hour, and is primarily eliminated through urine, with 20% excretion within 1 hour and 33% within 2 hours.

The study found that D-psicose accumulates only in the liver and not in the brain, indicating a specific organ distribution, and highlights the need for human trials to better understand its metabolism and potential applications.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Intestinal absorption, organ distribution, and urinary excretion of the rare sugar D-psicose. Tsukamoto, I., Hossain, A., Yamaguchi, F., et al.[2018]

The study indicates that intestinal transport of d-allulose is mediated by the glucose transporter type 5 (GLUT5), particularly enhanced in rats fed fructose, which increased GLUT5 expression.

When d-allulose is consumed with d-fructose, its absorption is reduced, suggesting that d-fructose competes with d-allulose for transport via GLUT5, indicating that d-allulose has a lower affinity for this transporter compared to d-fructose.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

d-Allulose is a substrate of glucose transporter type 5 (GLUT5) in the small intestine. Kishida, K., Martinez, G., Iida, T., et al.[2020]

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Safety Data Sheet

This product does not contain any chemicals known to State of California to cause cancer, birth defects, or any other reproductive harm. 16.