Effects of Body Composition on Vascular Health in Females with a Healthy Body Weight

Most of the time, body weight is evaluated by looking at the ratio of your weight to your height. This measurement is called body mass index or BMI. However, BMI does not account for what your body is actually made up of (e.g., body fat versus muscle), which may be more important for determining cardiovascular disease risk. The investigators aim to understand vascular health in females with a "healthy" BMI with differing amounts of body fat and muscle mass. We will have participants come to the lab for two different study visits. At one visit, participants will eat a meal high in fat, and at the other visit, participants will undergo a stress task.

The investigators will recruit females with a BMI in the normal (18.5-24.9 kg/m2) from the Ball State University campus and surrounding communities. Each participant will complete a meal trial and a stress trial in a randomized crossover design. At the meal trial, an intravenous catheter will be inserted and baseline blood sample collected. Then vascular measurements (i.e., flow-mediated dilation, pulse wave analysis, pulse wave velocity) will be performed. Each time vascular measurements are performed, the participants will lie in a quiet area to acclimate prior to beginning. Next, participants will consume a high-fat, Western style meal consisting of two Jimmy Deans Breakfast Bowls (sausage; 68 g fat; 880 kcal). Following completion of the meal, blood samples will also be collected 1, 2, 3, and 4 hours after the meal. Vascular measurements will be repeated 2 and 4 hours after the meal. Blood will be collected and stored as serum in order to measure triglycerides, HDL-C, and intestinal permeability (e.g., lipopolysaccharide binding protein) using commercially available ELISAs.

At the stress trial, an intravenous catheter will be inserted and baseline blood sample collected. Then vascular measurements (i.e., flow-mediated dilation, pulse wave analysis, pulse wave velocity) will be performed. Each time vascular measurements are performed, the participants will lie in a quiet area to acclimate prior to beginning. Next, participants will undergo the stress task. Then, blood samples will be collected at 10, 60, and 90 minutes after the stress task. Blood will be collected and stored as serum in order to measure epinephrine and inflammatory markers. Vascular measurements will also be repeated 10 and 90 minutes after the stress task.

Eligibility Criteria:
Inclusion Criteria:

* You are 18-50 years old
* Your biological sex is female
* BMI is in "normal" category (18.5-24.9 kg/m2) - this BMI requirement is due to our research aims
* You are not pregnant or expecting to become pregnant
* You are not postmenopausal
* You have not been diagnosed with a cardiometabolic condition (e.g., cardiovascular disease, type 2 diabetes)
* You have not been diagnosed with a chronic inflammatory condition (e.g., rheumatoid arthritis, inflammatory bowel disease).
* You do not regularly take anti-inflammatory drugs (more than 2x week) or are able to temporarily suspend use of anti-inflammatory drugs.
* You do not use lipid-lowering drugs (e.g., statins), glucose-lowering drugs (e.g., metformin) tobacco products, or any illicit drugs
* You do not have a pacemaker.
* You do not have dietary restrictions prohibiting you from eating the provided meal (e.g., vegan/vegetarian diets, gluten-free diet, relevant food allergies).
* You are able to stay in the supine position in the dark for at least 10 minutes

Exclusion Criteria:

* You are not 18-50 years old
* Your biological sex is not female
* Your BMI is not in the "normal" category (18.5-24.9 kg/m2) - this BMI requirement is due to our research aims
* You are pregnant or expecting to become pregnant (females only)
* You are postmenopausal
* You have been diagnosed with a cardiometabolic condition (e.g., cardiovascular disease, type 2 diabetes)
* You have been diagnosed with a chronic inflammatory condition (e.g., rheumatoid arthritis, inflammatory bowel disease).
* You regularly take anti-inflammatory drugs (more than 2x week) or are unable to temporarily suspend use of anti-inflammatory drugs.
* You use lipid-lowering drugs (e.g., statins), glucose-lowering drugs (e.g., metformin) tobacco products, or any illicit drugs
* You have a pacemaker.
* You do have dietary restrictions prohibiting you from eating the provided meal (e.g., vegan/vegetarian diets, gluten-free diet, relevant food allergies).
* You are unable to stay in the supine position in the dark for at least 10 minutes