This study is being conducted to determine the side effects related to LY3437943 given as a single injection under the skin to healthy participants. Blood tests will be performed to check how much LY3437943 gets into the bloodstream and how long the body takes to get rid of it. Each enrolled participant will receive a single dose of LY3437943 or placebo. The study will last up to approximately 71 days for each participant, including screening.

Inclusion Criteria:

• Overtly healthy male or a female who cannot get pregnant
• Have a body mass index (BMI) between 19 and 40 kilograms per square meter (kg/m²), inclusive, at screening
• Have normal blood pressure, pulse rate, electrocardiogram (ECG, heart tracing), blood and urine laboratory test results that are acceptable for the study
• Have veins suitable for ease of blood sampling

Exclusion Criteria:

• Are currently participating in or completed a clinical trial within the last 30 days or any other type of medical research judged to be incompatible with this study
• Have previously completed or withdrawn from this study
• Smoke more than the equivalent of 10 cigarettes per day and are unwilling to stop smoking during the inpatient stay in the study
• Have or used to have health problems or laboratory test results or ECG readings that, in the opinion of the doctor, could make it unsafe to participate, or could interfere with understanding the results of the study
• Have been treated with weight loss medications within 3 months of screening