Fasting Insulin

What is insulin?

Insulin is a hormone secreted primarily by the pancreas that is mainly responsible for regulating blood glucose levels. After eating, insulin is released to initiate the usage and storage of glucose. 

Why is fasting insulin included in the metabolic axis?

According to the CDC, about 1 in 10 Americans have diabetes, and about 1 in 5 people with diabetes don't know they have it! High insulin levels can be a leading indicator of pre-diabetes and metabolic syndrome. Type 1 diabetes is an autoimmune disease caused by insufficient production of insulin by the pancreas, whereas type 2 diabetes is a metabolic disease caused by insulin resistance to high levels of circulating glucose. Gestational diabetes is another type that develops in pregnant women and can have negative implications for the health of the baby. While insulin is a necessary data point for those with diabetes, it is also very useful for users without these concerns. Insulin levels can serve as a great indicator of your body’s reaction to your current diet and lifestyle. Because of its significance to metabolic health, insulin is included in SiPhox Health's base panel.

How can I better understand my results?

Insulin follows a natural circadian rhythm, so sticking to a routine (e.g. eating at the same time every day) can help maintain optimal metabolic levels throughout the day.

Make sure your insulin levels are within the recommended range if you take your test without fasting. We recommend you test in a fasted state (no food or beverages besides water for 8 hours prior to testing). When fasting, you can expect the following insulin levels:

Optimal: 2-5 uIU/mL

Normal: < 8 uIU/mL

Fasting insulin levels that are higher than normal can be indicative of insulin resistance. Insulin resistance is when the body fails to respond to insulin by taking up glucose, so more insulin is secreted to compensate. Due to the natural rise and fall of insulin throughout the day in anticipation of food, the time of day and your fasting state can influence results. Consult with your physician if you are concerned about your insulin levels. 

Symptoms of insulin resistance include:

  • Increased thirst
  • Frequent urination
  • Increased hunger
  • Blurred vision or eye changes
  • Headaches
  • Vaginal and skin infections
  • Slow-healing cuts and sores
  • Darkened skin in your armpit, back, or sides of your neck (acanthosis nigricans)
  • Skin tags

If your insulin levels are high, you can try:

  • Lose weight by leading a healthy lifestyle
  • Exercise and build muscle
  • Avoid highly processed, high-carbohydrate foods and saturated fats
  • Opt for low glycemic index foods (beans and legumes, non-starchy veggies, berries, etc.)

Hormonal disorders such as Cushing's syndrome, acromegaly, and hypothyroidism, and genetic disorders can cause insulin resistance. Certain medications can cause insulin resistance as well, which is why you should consult with your physician if you are concerned about your levels.

Where can I learn more?

American Diabetes Association - Insulin Basics

Cleveland Clinic - Insulin Resistance

NIH - Circadian Regulation of Glucose, Lipid, and Energy Metabolism in Humans