Over the past six newsletters I have delved into the importance of mitochondrial health and how certain interventions like exercise, infrared light, and nutritional supplements can improve its function. But how do we know if we have a mitochondrial problem to begin with? Is there a test to see if the mitochondria are weak and is there a way of measuring if they are improving?
Indirect Calorimetry:
There is no perfect way to measure mitochondrial health, but if there were a best choice available it would be indirect calorimetry. Indirect calorimetry is a method that measures the respiratory gases oxygen and carbon dioxide to determine what someone’s metabolic rate is. More simply it measures resting metabolic rate (RMR) or resting energy expenditure (REE), which determines the number of calories needed by a person to live. RMR and REE can be used interchangeably. By analyzing these parameters of breath analysis and knowing the level of activity a person has during the day, you could tailor a diet specifically for that person. If you wanted someone to maintain their weight you would want to know the calories needed to perform their physical activity and the calories needed for their resting metabolic rate to equal the number of calories consumed. RMR is in large measure related to the health of the mitochondria because it represents the burn rate of your caloric needs.
Traditionally, indirect calorimetry (IC), is used in hospitals for those in intensive care units for those who may be comatose to determine their caloric needs. It is also used in research facilities such as in a sports evaluation lab settings to determine the caloric needs of top tier athletes. These two scenarios require a metabolic cart with instrumentation that can cost in the thirty-to-sixty-thousand-dollar range, putting this technology out of reach to the average person.
There are “bio-hacking” companies who are competing to win the race to measure these respiratory gases in a cost-effective way to capture the market for the average consumer. Remember - the mitochondria are responsible for powering the body with the production of ATP, so if you could more accurately measure your metabolic rate you could adjust your calorie intake accordingly. Presently, calorie recommendations are based on formulas provided by activity trackers, BMI measurements, body composition analysis, or the body mass index. These measurements can be misleading and this video explains why. The analogy they use for two Italian cars, a Ferrari, and an e-Fiat of equal age and weight and the assumption that each would thrive on equal amounts of gas per day is pertinent to the discussion of caloric needs between the two women of equal age and weight in the video. It explains why a person with their own unique RMR or REE, might fail in their attempts to regulate their weight.
This link is to the Harris-Benedict equation for calculating RMR without measuring respiratory gases. While this does provide a ballpark idea of where someone’s calorie intake should be each day, it is accuracy might be like the example of the two Italian cars and women in the video.
In a book Bursting with Energy by Dr. Frank Shallenberger, he talks of the advantages of having an efficient RMR and its association with longevity. In mice with a healthier RMR, they lived 36% longer. RMR declines with disease, loss of muscle mass, poor sleep quality, poor diet, abnormal hormone levels, low B vitamins, coenzyme Q10, fatty acids and magnesium. Shallenberger also talks about the carbon dioxide to oxygen ratio (CO2/O2) and its applicability to evaluating mitochondrial health.
The Carbon Dioxide/Oxygen ratio or Respiratory Exchange Ratio (RER) or RQ Respiratory Quotient. These can all be used interchangeably.
This is where the rubber meets the road regarding mitochondrial health. The amount of CO2 produced when breathing is in direct proportion to the amount of energy (ATP’s) produced by either fat or glucose. The more carbon dioxide being measured in respiration would indicate a higher reliance of carbohydrates for fuel. Therefore: A measurement of a RER of 0.7 indicates that fat is the predominant fuel source and an RER of 1.0 or higher indicates that carbohydrates are the predominant fuel source. A RER in between indicates a mixture of both fat and carbohydrate. What follows below may initially seem confusing, but if you follow the color coding, it makes it simpler.
Utilization (oxidation) of a carbohydrate molecule:
6 O2 molecules + carbohydrate à 6 CO2 + 6 H2O + 38 ATP = 6.3 O2 per ATP
RER = CO2/O2 = 6 CO2/6 O2 = 1.0
Utilization (oxidation) of a fat molecule:
23 O2 molecules + fatty acid à 16 CO2 + 16 H20 + 129 ATP = 5.6 O2 per ATP
RER = CO2/O2 = 16 CO2/23 O2 = 0.7
With carbohydrates you need 6 oxygen molecules to make 38 ATP. You are then producing 6.3 ATPs for each molecule of oxygen when eating a molecule of carbohydrate.
In comparison:
With fats if you need 23 molecules of oxygen to make 129 molecules of ATP. You are then producing 5.6 ATPs for each molecule of fat.
By this analysis, carbohydrates would appear to be a better fuel source for energy because you can produce more ATPs between equal amounts of carbohydrates and fats. So, subsisting on a diet high in carbs is best for the mitochondria? Not exactly. This only indicates how your body would best respond to a sudden need for energy for an emergency where you would max out your ATP demands such as during a high intensity race or workout (VO2 max) and correlates with the practice of carbohydrate loading before a race. During inactive moments in our lives, it would make more sense to be deriving our energy from fat. Think about how much gas that Ferrari consumes while idling at a traffic stop and how inefficient that is. If someone at rest has a RER of 1.0 or higher, this is a sign that their mitochondria are inefficient. Ideally, a RER would be closest to 0.7 and being able to tap into fat reserves for energy when at rest or in a fasted state. Most of us live in the area between .7 and 1.0, but the closer we live to the .7 mark is indicative of a more efficient energy system which is in large part due to well-functioning mitochondria being able to produce ATP’s when we need them for movement and powering our immune system.
Final Thoughts
The best-known bio-hacking device for measuring respiration for dietary needs is the Lumen. However, it only measures carbon dioxide, and not oxygen and without that measurement, it falls short in accuracy. I am investigating other devices that measure both oxygen and carbon dioxide and even though their cost is far less than a medical metabolic cart they still can cost a few thousand dollars. There is one company that I am looking at that has a unit for under 500.00 and if I get a chance to evaluate it, I will write about it in a forthcoming newsletter. Presently they are out of stock.
The important idea that I wanted to convey is that each of us burns calories differently from one another. Using respiratory analysis not only gives us a tool to determine our individuality in this area, it also is a strong correlator for evaluating the calorie burning and ATP producing apparatus inside our cells – the mitochondria.
