Which biomarkers does Tim Ferriss regularly track?
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A biomarker is a measurable substance that is indicative of some phenomena such as disease, infection, or environmental exposure. Biomarkers can be used to track how the body is responding to a dietary intervention or exercise program. To assess his body's response to the ketogenic diet, Tim routinely measures his blood ketone level - observing that his level of blood ketones closely reflects his state of mental clarity. Tim also tracks additional biomarkers including glucose level, hemoglobin A1c, sex hormones, and numerous other parameters. In this clip, Tim Ferriss describes the biomarkers that he tracks to fine-tune his health and mental well-being.
- Tim: But when I am focused on at least a nominal amount of ketones, I feel like my old self. So that's one. Other things that I focus on or look at . . . there are some esoteric things that I play with every once in a while. But if you're looking at the routine levels, I'm going to look at obviously the sex hormones, look at free testosterone. I'll look at free testosterone as relative to sex hormone binding globulin, for instance. I'm not convinced that higher sex hormone binding globulin is always a bad thing. That's a whole separate. Because my testosterone in experimenting with high fat, total testosterone has gone from 650 to 950 in a span of nine months. It's a non-trivial increase. Now, sex hormone binding globulin has also increased over time. But I've gained so much lean muscle tissue that I have other ideas. I was talking to Steven Phinney about this--scientist, very well known for looking at the ketogenic diet--and what he was saying is independent of insulin levels, insulin made very anabolic . . . sorry, we're getting into the weeds here. It's possible that my lean mass gains can be account for by decreased degradation of branch chain amino acids. I was like, "That's really interesting." Maybe that explains by fasting plus chemotherapy is very, very effective, for instance. People can recover faster from chemotherapy. So you have the ketones. You have the sex hormones. Hemoglobin A1c, sort of like your running three-month average of glucose levels just as an insurance policy to ensure that I'm not skewing towards pre-diabetic in any way. And then a laundry list of like five or six different pages of stuff.
- Rhonda: So your biomarkers tend to be a lot of performance-related biomarkers.
- Tim: Yeah.
A measurable substance in an organism that is indicative of some phenomenon such as disease, infection, or environmental exposure.
A blood test that measures the amount of glycated hemoglobin in a person’s red blood cells. The hemoglobin A1c test is often used to assess long-term blood glucose control in people with diabetes. Glycation is a chemical process in which a sugar molecule bonds to a lipid or protein molecule, such as hemoglobin. As the average amount of plasma glucose increases, the fraction of glycated hemoglobin increases in a predictable way. In diabetes mellitus, higher amounts of glycated hemoglobin, indicating poorer control of blood glucose levels, have been associated with cardiovascular disease, nephropathy, neuropathy, and retinopathy. Also known as HbA1c.
A peptide hormone secreted by the beta cells of the pancreatic islets cells. Insulin maintains normal blood glucose levels by facilitating the uptake of glucose into cells; regulating carbohydrate, lipid, and protein metabolism; and promoting cell division and growth. Insulin resistance, a characteristic of type 2 diabetes, is a condition in which normal insulin levels do not produce a biological response, which can lead to high blood glucose levels.
A diet that causes the body to oxidize fat to produce ketones for energy. A ketogenic diet is low in carbohydrates and high in proteins and fats. For many years, the ketogenic diet has been used in the clinical setting to reduce seizures in children. It is currently being investigated for the treatment of traumatic brain injury, Alzheimer's disease, weight loss, and cancer.
Molecules (often simply called “ketones”) produced by the liver during the breakdown of fatty acids. Ketone production occurs during periods of low food intake (fasting), carbohydrate restrictive diets, starvation, or prolonged intense exercise. There are three types of ketone bodies: acetoacetate, beta-hydroxybutyrate, and acetone. Ketone bodies are readily used as energy by a diverse array of cell types, including neurons.
A health condition in which blood glucose levels are higher than normal, but not high enough to indicate a diagnosis of type 2 diabetes. Prediabetes can be halted or reversed with dietary and lifestyle modifications, including weight loss, exercise, and stress reduction.
A glycoprotein that binds to sex hormones, and is produced mostly by the liver. Testosterone and estradiol circulate in the bloodstream bound mostly to SHBG. Only around 1-2% is unbound or "free", and thus biological active. The relative binding affinity of various sex steroids for SHBG is dihydrotestosterone (DHT) > testosterone: androstenediol> estradiol> estrone.
The primary male sex hormone. Testosterone is critical to the maintenance of fertility and secondary sexual characteristics in males. Low testosterone levels may increase risk of developing Alzheimer’s disease.
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