Heart Rate Variability (HRV)

 

Heart Rate Variability (HRV)

• What it measures: The variation in time intervals (in milliseconds) between consecutive heartbeats — not the average rate, but how much the timing between beats fluctuates.
  • Even at a steady 60 bpm, the time between beats isn't perfectly 1,000 ms each time — it might be 980 ms, then 1,020 ms, then 995 ms, etc. HRV quantifies that tiny beat-to-beat variation.
• What it tells you: A window into your autonomic nervous system balance (especially parasympathetic "rest-and-digest" vs. sympathetic "fight-or-flight" activity).
  • Higher HRV → generally better recovery, more resilience to stress, stronger parasympathetic activity, better overall adaptability.
  • Lower HRV → often indicates stress, fatigue, overtraining, poor recovery, inflammation, or aging effects.
• It's a much more sensitive indicator of recovery status, nervous system health, and subtle stress than HR alone.

HR vs. HRV -- Quick Comparison

Aspect	Heart Rate (HR)	Heart Rate Variability (HRV)
Unit	Beats per minute (bpm)	Milliseconds (ms) between beats
What it actually tracks	Average number of beats	Variation / irregularity in beat timing
Main physiological insight	Level of cardiac demand / exertion	Autonomic nervous system balance & recovery
Typical healthy range (rest)	50–90 bpm (varies by age/fitness)	Higher = better (e.g., 40–100+ ms depending on metric, age, device)
Changes with stress	↑ (increases)	↓ (decreases)
Changes with good recovery/fitness	↓ (decreases)	↑ (increases)
Measurement precision needed	Low	High (needs accurate beat detection)

In short:

• HR is like checking how fast your car is going right now.
• HRV is like checking how smoothly and adaptively the engine is responding to tiny throttle changes.

Boron

Boron is a trace element that is naturally present in many foods and available as a dietary supplement. 

Boron is not classified as an essential nutrient for humans because research has not yet identified a clear biological function for boron . However, it might have beneficial effects on such functions as reproduction and development, calcium metabolism, bone formation, brain function, insulin and energy substrate metabolism, immunity, and the function of steroid hormones (including vitamin D and estrogen).

• more at https://ods.od.nih.gov/factsheets/Boron-HealthProfessional/

The U.S. Department of Agriculture’s (USDA’s) FoodData Central does not list the boron content of foods or provide lists of foods containing boron. Therefore, information on boron levels in foods is limited.

Boron Content of Selected Foods

Food	Milligrams (mg) per serving
Prune juice, 1 cup	1.43
Avocado, raw, cubed, ½ cup	1.07
Raisins, 1.5 ounces	0.95
Peaches, 1 medium	0.80
Grape juice, 1 cup	0.76
Apples, 1 medium	0.66
Pears, 1 medium	0.50
Peanuts, roasted, salted, 1 ounce	0.48
Beans, refried, ½ cup	0.48
Peanut butter, 2 tablespoons	0.46
Apple juice, 1 cup	0.45
Chili con carne, with beans, 1 cup	0.41
Grapes, ½ cup	0.37
Oranges, 1 medium	0.37
Lima beans, dry, cooked, ½ cup	0.35
Applesauce, ½ cup	0.34
Fruit cocktail, canned, in heavy syrup, ½ cup	0.26
Broccoli, boiled, chopped, ½ cup	0.20
Orange juice, 1 cup	0.18
Spinach, boiled, ½ cup	0.16
Banana, medium	0.16
Spaghetti sauce, ½ cup	0.16
Cantaloupe, cubed, ½ cup	0.14
Carrots, raw, 1 medium	0.14
Peas, green, cooked, ½ cup	0.10
Potato chips, 1 ounce, about 22 chips	0.09
French fries, from frozen, deep fried, 10 fries	0.08
Coffee, 1 cup	0.07
Lettuce, chopped, loosely packed, 1 cup	0.06
Tomatoes, raw, chopped, ½ cup	0.06
Tuna, canned, water packed, 3 ounces	0.05
Milk, whole, 1 cup	0.04
Corn, cooked, ½ cup	0.04
Rice, white, cooked, ½ cup	0.03
Chicken breast, broiled, ½ breast	0.03
Tea, brewed, 1 cup	0.02
Onions, raw, chopped, 1 tablespoon	0.02
Ice cream, ½ cup	0.02
Bread, white, 1 slice	0.01

 

Retatrutide

Retatrutide (LY3437943) is an investigational injectable drug from Eli Lilly, a triple hormone agonist activating GIP, GLP-1, and glucagon receptors.

Similar to other GLP-1 medications, retatrutide is an injectable medication that targets hormone receptors in your body that directly impact metabolism and appetite. Retatrutide targets three different receptors: 

• GLP-1 (helps regulate appetite and blood sugar)
• GIP (supports insulin response)
• Glucagon (affects energy use and fat metabolism)

By targeting all three, the medication delays how fast your stomach digests food, lowers your appetite, and ultimately reduces how much food you eat. This can lead to numerous improvements in health, including: 

• Weight loss
• Improved glycemic control (a.k.a. how well your blood sugar is managed)
• Lower blood pressure
• Better liver and kidney health

 

But retatrutide does still carry the risk for side effects that most in this category do, most commonly GI issues like nausea, constipation, or vomiting. While higher doses of retatrutide are linked to more weight loss, dosing is titrated up over time, just like with other injectables.