Lean and Obese: Dietary Inflammation

Not Applicable

Completed

• Conditions: Obesity; Inflammation; Dietary Fat
• Interventions: Other: Low Fat Diet (LFD); Other: High Fat Diet (HFD)

• Registration Number: NCT05327868
• Lead Sponsor: Rutgers, The State University of New Jersey

Brief Summary

In the Lean and Obese Dietary Inflammation (LODI) study, the primary goal is to determine the effect of short-term intake of high dietary fat (5 days) compared to low fat intake (5 days) in a cross-over design in older adults (men and women) with normal body weight or obesity. Inflammation will be examined by measuring serum endotoxin and other markers, as well as the fecal microbiota.

Detailed Description

In the Lean and Obese Dietary Inflammation (LODI) study, short-term intake of a high-fat diet (HFD) that is also high in saturated fatty acids will be examined compared to a low-fat diet (LFD) in individuals who are normal body weight (BMI 19.5-24.9) or who have obesity (BMI of 30 - 40 kg/m2). To characterize persons at baseline, this study will examine body composition, and serum glucose, endotoxin, inflammation and intestinal permeability during fasting and in response to a mixed meal. Also, while it is known that long term intake of foods affects the microbiota, it is unclear whether short-term consumption of a HFD will shift towards a pro-inflammatory gut microbiota compared to a low fat intake. This will be tested in a cross-over design (5 days on a HFD, washout, and 5 days on a LFD) with order randomly assigned in older adults (50+ years of age) who have obesity or are normal weight, and will also be examined by estimated visceral adipose tissue level.

Study Timeline

• Study First Submitted: 2022-02-28
• Study Start: 2022-03-01
• Study First Submitted QC: 2022-04-07
• Study First Posted: 2022-04-14
• Primary Completion: 2023-01-01
• Study Completion: 2023-02-11
• Status Verified: 2024-03
• Last Update Submitted: 2024-03-21
• Last Update Posted: 2024-03-25

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 32

Inclusion Criteria

• Men or Women
• Age 50-79 years (only postmenopausal women > 2 years)
• Body mass index (20-25 kg/m2; and 30-40 kg/m2)*

Exclusion Criteria

• Diagnosed with, active, or history of liver cirrhosis, chronic or persisting hepatitis

• Diagnosed with, active, or history of cancer

• History of gastrointestinal disease or surgical procedure for weight loss.

• Diagnosed with immune diseases, type 2 diabetes, pancreatitis, or infectious diseases

• Any surgery in the past 6 months

• Currently using or have used antibiotics continuously > 3 days in the past 3 months

• Regular use of medications for that affect the gastrointestinal tract, cholecystitis, urinary tract infection, severe organic diseases including coronary heart disease, myocardial infarction, infectious diseases including pulmonary tuberculosis and AIDS

• Known allergy or intolerance to any ingredients in the dietary intervention program

• Alcohol or illicit drug abuse

• Current Smoker or have quit smoking in the past 3 months

• Recent colonoscopy (within the previous two months)

• Inability to follow any of the experimental diets (including low or high fat diet) or to perform the collections required for this study

• Participants will also be excluded if they have extreme dietary habits, extreme levels of physical or athletic activity, or by changes in body weight >5 lbs. during the last 6 months

• Uncontrolled hypertension or uncontrolled hyperlipidemia in abnormal ranges.

• Participation in another clinical research trial that may interfere with the results of this study.

  • As needed, BMI (kg/m2) will be adjusted accordingly for Asian lean and obese definitions

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Normal weight (lean)	High Fat Diet (HFD)	Normal body weight
Obese	Low Fat Diet (LFD)	BMI in Obesity range
Obese	High Fat Diet (HFD)	BMI in Obesity range
Normal weight (lean)	Low Fat Diet (LFD)	Normal body weight

Primary Outcome Measures

Name	Time	Method
Change in Endotoxin from Low to High fat diet	Change from LFD (5 days) to HFD (5 days) over an average of 6 weeks	serum and stool
Change in Microbiome composition	Change from LFD (5 days) to HFD (5 days) over an average of 6 weeks	stool

Secondary Outcome Measures

Name	Time	Method
Zonulin	Change from LFD (5 days) to HFD (5 days) over an average of 6 weeks	Serum
Inflammatory markers	Change from LFD (5 days) to HFD (5 days) over an average of 6 weeks	Serum IL-6, hsCRP, TNF-alpha, TLR4 (grams/volume)
Lipopolysaccharide binding protein (LBP)	Change from LFD (5 days) to HFD (5 days) over an average of 6 weeks	Serum
Toll like receptor-4 and Null 2 stimulation	Change from LFD (5 days) to HFD (5 days) over an average of 6 weeks	serum and the HEK cell reporter assay
Endotoxin in response to a meal	Change over 5 hour MMT	Serum inflammatory response to a mixed meal tolerance test (MMT)

Trial Locations

Locations (1)

Rutgers University; 🇺🇸 New Brunswick, New Jersey, United States