Track topics on Twitter Track topics that are important to you
This study will try to determine if intake of dietary fats or carbohydrates influences the tendency to gain weight or accumulate body fat. It will examine how the hormones that regulate weight may change with a shift from a balanced diet to one that is low in fat or carbohydrate, irrespective of caloric intake.
Men and women between the ages of 18 and 40 years with a body mass index of 30 to 49 kg/m2 may be eligible for this study. Candidates will be screened with a history, physical examination, blood tests and questionnaires regarding activity, prior diets, and eating patterns.
Participants will follow two separate diet regimens for 5 days each. The first will be a balanced diet, and the second will be either a low-fat/high-carbohydrate diet or a low-carbohydrate/high-fat diet. The diets are not designed to produce weight loss. Participants will receive all their meals and snacks for the two diets from the National Institutes of Health and, for the first 3 days of each diet, will be seen as outpatients. For days 4 and 5 of each diet, they will be admitted to the Clinical Center and will undergo the following procedures:
- Blood tests - Blood samples will be collected every 30 minutes over a 24-hour period through an indwelling catheter in the arm. A total of about 15 tablespoons will be drawn for each of the two diets.
- 24-hour urine collection - One 24 hour urine collection will be done at home the day before admission to the Clinical Center, and the other will be done during the hospital stay.
- Urinalysis and pregnancy test - A small urine sample will be taken and women will provide an additional sample for a pregnancy test.
- Body measurements - Height and weight will be measured using scales. Body fat will be measured by two methods: skin fold thickness, measured with calipers in 5 separate places; and body circumference measurements, in which body parts are measured with a tape measure.
- Bod pod measurement - Proportions of fat and non-fat tissue in body weight are measured while the participant sits in a capsule-like device for 5 minutes.
- Bioelectric impedance analysis - Proportions of body fat are measured based on conduction of a small electric current.
- Total body water estimate -The proportion of body weight that is water is determined, using a method that involves drinking a cup of a special kind of "heavy" water (deuterium) and then measuring the amount of heavy water in a urine sample taken after 4 hours.
- Exercise - Participants will maintain their usual exercise routine, as it was before beginning the study.
Caloric restriction triggers a number of homeostatic endocrine responses including suppression of leptin, gonadotropins, sex steroids, thyroid hormones, insulin and insulin like growth factors (IGFs) and elevation of growth hormone (GH) and cortisol. Some of these effects may be disadvantageous in terms of achieving loss of adipose tissue. There is little information on the role of specific macronutrients in the regulation of these important endocrine responses to food restriction. The present study aims to determine if dietary carbohydrate and/or lipid composition has significant effects on these hormonal regulators of body composition and metabolism, independent of total calorie supply. This will be achieved by comparing the short-term effects of isocaloric, weight maintenance diets restricted in either fat or carbohydrate with a standard balanced diet. Protein contribution as well as calorie content will be held constant in the 3 diets. Study subjects will be obese women and men (BMI 30-34.9 kg/m2) aged 18-40 years. Major study outcome parameters include: leptin, gonadotropin, GH and cortisol secretory dynamics; sex steroid, IGF, fasting insulin and glucose levels.
National Institute of Child Health and Human Development (NICHD)
National Institutes of Health Clinical Center (CC)
Published on BioPortfolio: 2014-08-27T03:56:54-0400
Healthy Together is a program that promotes the achievement and maintenance of healthy weights in children and their families.
Investigators conducted a pilot feasibility and acceptability randomized controlled trial of a remotely delivered behavioral health coaching program in pregnancy and postpartum.
Absorption, distribution, metabolism, and excretion (ADME) study with 14C in healthy young men.
The purpose of this study is to understand how consuming healthy cookies every day for two weeks will affect different types of fat in the blood. Specifically, the overall goal of this stu...
To assess the safety, tolerability, pharmacokinetics, and pharmacodynamics of IMA-026 administered subcutaneously (SC) or intravenously (IV) in healthy adults.
Using an operational continuum of healthy aging developed by U.S. researchers, we sought to estimate the prevalence of healthy aging among older Spaniards, inform the development of a definition of he...
The American Nurses Association declared 2017 the Year of the Healthy Nurse. In an effort to promote a healthy academic environment, faculty and staff in institutions of higher learning should serve a...
China has the largest population in the world, and its health levels have greatly affected the healthy development of the population of the world. Healthy China 2030 is a breakthrough for ensuring tha...
Across Ontario, the Healthy Babies Healthy Children (HBHC) postpartum screening tool is routinely used to identify families with potential risk of negative development outcomes for children.
Sequence-specific learning (SSL); the ability to implicitly integrate repeated sequences compared to random sequences during a motor sequence paradigm, is impaired in healthy elders (HE) compared to h...
Healthy People Programs are a set of health objectives to be used by governments, communities, professional organizations, and others to help develop programs to improve health. It builds on initiatives pursued over the past two decades beginning with the 1979 Surgeon General's Report, Healthy People, Healthy People 2000: National Health Promotion and Disease Prevention Objectives, and Healthy People 2010. These established national health objectives and served as the basis for the development of state and community plans. These are administered by the Office of Disease Prevention and Health Promotion (ODPHP). Similar programs are conducted by other national governments.
Governmental guidelines and objectives pertaining to public food supply and nutrition including recommendations for healthy diet and changes in food habits to ensure healthy diet.
Surgical reinnervation of a denervated peripheral target using a healthy donor nerve and/or its proximal stump. The direct connection is usually made to a healthy postlesional distal portion of a non-functioning nerve or implanted directly into denervated muscle or insensitive skin. Nerve sprouts will grow from the transferred nerve into the denervated elements and establish contact between them and the neurons that formerly controlled another area.
Process of evaluating the health of a patient and determining if they are healthy enough for surgery.
Dietary patterns which have been found to be important in reducing disease risk.
Women's Health - key topics include breast cancer, pregnancy, menopause, stroke Follow and track Women's Health News on BioPortfolio: Women's Health News RSS Women'...
Within medicine, nutrition (the study of food and the effect of its components on the body) has many different roles. Appropriate nutrition can help prevent certain diseases, or treat others. In critically ill patients, artificial feeding by tubes need t...