Hormonal Regulation of Postpartum Weight and Presence of Gut Peptides in Human Milk

Inclusion Criteria:

• Healthy women (non-smokers) at least 18 years old who did not have any pregnancy complications, and gave birth to their first child within one month.
• The study is open to women who are breastfeeding or formula feeding.

Exclusion Criteria:

• Smoker,
• had twins or triples,
• had any major complication of pregnancy(example,
• gestational diabetes);
• have kidney, liver, hormonal, stomach, intestine,lung, heart or blood disease. This also includes high blood pressure;
• use prescription or over-the-counter medicine or herbal drinks or pills.
• History of depression, anxiety, disordered eating, other psychological problems, alcoholism or other substance abuse.
• Severely claustrophobic.
• Having a strong fear of needles and/or do not feel you can have blood drawn every 30 minutes from a plastic catheter.
• Are not able to or willing to fully participate in the study, and are pregnant, anemic or have a thyroid problem.