The Quantified Self: What To Measure and Why It Matters

The quantified self movement isn’t something you sign up for. If you’re the kind of person who tracks sleep, macros, and blood work, then congratulations: you’re part of it.

Your friends and family might not understand. Must every health metric be quantified?

Well, not every metric. That amount of lab testing would entail a serious wallet-ectomy. 

But the important ones, yes. By measuring these metrics—many of which we’ll cover in a moment—you discover where you need to improve. But there’s more to it than that.  

Quantified Self 101

You can quantify most aspects of your health. You can quantify your sleep, diet, exercise, metabolic health, heart health, gut health, and even your DNA. 

By tracking your crucial health metrics, you can take steps to improve overall wellbeing. That’s the basic concept behind the quantified self movement.

This sentiment is reflected in the old business adage: “what gets measured gets managed.” If you don’t measure something, how can you work to improve it?

Quantifying health metrics also increases personal accountability. In a sense, you’re on the hook for your sleep score, blood glucose levels, inflammation biomarkers, etc. 

If you do something that disrupts these metrics, your accountability kicks in. An example will help illustrate. 

Let’s say you stay up late watching a movie. You could have saved it for later, but you kept watching anyway. Oh well. We all make mistakes, especially when Ryan Gosling is involved. 

But your sleep tracker won’t let you off so easily. Your sleep score will drop, and you’ll want to make it right. That’s accountability.

Or take another example: tracking your carb intake. The mere knowledge of your carb limit will discourage you from reaching into the cookie jar like an impulsive toddler. 

Quantifying your health is like playing the most important video game you’ll ever play. Every time your score improves, your health wins. 

And when your metrics aren’t where you’d like them to be, that’s valuable info too. It tells you where to focus your efforts. Measure, tinker, measure, tinker, rinse and repeat. 

9 Health Areas to Quantify

If you can think of it, you can quantify it. Here are nine key health areas to quantify, along with practical tips, solutions, and product recommendations. 

#1: Diet

To optimize your diet, you might track:

• Macronutrients (carbs, protein, and fat)
• Micronutrients (vitamins, minerals, and fatty acids)
• Calories
• Your intermittent fasting schedule

Take the Keto diet, for example. Succeeding on Keto means limiting carbs to 5 or 10 percent of your daily calories, and limiting carbs (at least initially) requires a macro tracker. 

Recommendation: Use the Carb Manager app for food logging, macro tracking, micro tracking, and all other aspects of quantified nutrition. 

#2: Sleep

Sleep is a critical pillar of health. Even partial sleep deprivation can derail your focus, metabolic health, immunity, mood, and more.[*][*][*][*] Sleep disruptions can even affect your hunger by leading to increased levels of ghrelin, the hunger hormone.[*]

There are three main categories to quantify with sleep:

1. Sleep quality (deep sleep, REM sleep, number of wakeups)
2. Sleep quantity (how long you sleep)
3. Sleep schedule (are you entering and exiting the sack at the same time each day?)

Recommendation: Apple Watch, Fitbit, Garmin, and Google Fit can all be integrated with the Carb Manager app for sleep tracking. Whoop is also a sleek option in this space. 

#3: Heart activity

Many wearables also measure the activity of your heart. These measures include:

• Heart rate variability: a marker of nervous system health[*]
• Resting heart rate: lower is generally better
• Heart rate during exercise

Recommendation: Check out Whoop, Fitbit, or Apple Watch for heart rate activity tracking. 

#4: Exercise

Tracking exercise performance can motivate you. If your 5k time keeps improving, it’ll keep you coming back for more. 

Measuring your heart rate during exercise also provides useful data for modulating your training schedule. A good rule of thumb? Most of your exercise should occur below 70% of your max heart rate, with brief forays into higher intensity efforts. 

Recommendation: Apple Watch, Fitbit, and Google Fit can all be integrated with the Carb Manager app for exercise tracking.  

#5: Body measures

Along with body weight, consider tracking:

• Waist circumference
• Body fat percentage
• Muscle percentage

The gold standard for measuring body fat vs muscle (body composition) is the DXA scan, but you can also assess this metric by looking in the mirror. 

#6: Gut health 

Can you quantify your gut microbiome? Yes and no. 

You can catalog the various microbes in your gut, but the health applications of doing so are unknown. Everyone’s gut is different, and a bacterium that might be good for one person might be bad for you. 

Recommendation: Companies like Viome can sequence your microbiome and offer food, nutrient and supplement recommendations based on your results.

#7: Metabolic health

Measuring glucose and ketones provide a snapshot of your metabolic health. Optimal glucose levels (for minimal diabetes risk) are likely below 85 mg/dl[*], and optimal ketone levels (for nutritional ketosis) are likely between 0.5 mmol to 3.0 mmol BHB. Your primary care physician, obesity medicine specialist, or endocrinologist may order blood tests (i.e. HbA1c, fasting insulin, etc.) in order to help determine your metabolic health status. More on these below.

Recommendation: Try the Keto-Mojo meter for measuring glucose and ketones in the blood. To measure metabolic status via the breath, check out the Lumen device.

#8: Lab work

If you ordered every possible lab test, you’d soon receive a concerned phone call from your credit card company. Economize that process and start with these instead:

• Heart health biomarkers like LDL cholesterol, HDL cholesterol, triglycerides, and ApoB[*]
• Inflammation biomarkers like CRP, homocysteine, ESR and fibrinogen
• Liver health biomarkers like ALT, AST, and GGT
• Kidney health biomarkers like creatinine and EGFR
• Metabolic health biomarkers like fasting blood glucose, fasting insulin, and HbA1c
• Blood health biomarkers like hemoglobin, red blood cell count, platelets, and white blood cell count
• Vitamin D levels (important for most aspects of health, including COVID-19 prevention and mitigation[*][*])

Recommendation: Check out SelfDecode. This science-backed personalized service helps you order, interpret, and monitor lab work.

#9: DNA

In 2003, scientists wrapped up the Human Genome Project. It had taken 13 years, but the human genome had finally been sequenced. 

Today it doesn’t take 13 years to sequence your genome. It doesn’t even take 13 days. And while we’re still largely ignorant of how our genes influence our health, we know enough to make it worth the hassle. 

Consider, for instance, the APOE gene. Mutations on this gene can significantly multiply (or downgrade) your risk for Alzheimer’s disease.[*] 

Recommendation: Map your DNA using a service like 23andMe, then upload the data to SelfDecode for personalized health analysis. 

Quantifying Yourself for Better Health 

Most people don’t quantify their health. If their doctor hasn’t ordered it, they aren’t going to think about it. 

Health is just something that happens to them, like the weather. There’s no sense of control. 

Quantifying your health puts you in the driver’s seat. You have a handle on your metrics, and you’re doing something about them. 

Long-term, this effort will serve you well. Keep it up. 

Disclaimer: This article contains affiliate links. Carb Manager may earn a commission for qualifying purchases made through these links.