The Mitochondria

I’d liked to introduce you to someone, or technically something, your mitochondria. These organelles are so crucial for our health that if we are interested in warding off and healing from disease, which I believe most of us are, it is critical for us to learn more about them. Mitochondria are tiny organelles which are any number of organized or specialized structures within a living cell that operate like organs carrying out specific tasks. Therefore, you could think of these as micro-organs. One of the primary and vital roles mitochondria play are producing energy by combining nutrients from the sugars and fats we eat with oxygen from the air we breathe. The energy particles created by the mitochondria are called Adenosine Triphosphate (ATP). They are able to incredible amounts of this ATP. How much? About 110 pounds of ATP every day!1

They May Be Small, But There are Many

Mitochondria are incredibly small but yet they can manufacture enormous amounts of ATP. This is because what they lack in size they make up for in sheer numbers. Researchers estimate that there are approximately 10 million billion or one hundred quadrillion (1017) within the cells of an average adult.2 These are nearly unfathomable numbers to comprehend, but consider this, more than 1 billion mitochondria could fit on the head of a pin. All these mitochondria account for 10 percent of the average person’s body weight. The number of mitochondria vary from cell to cell. For example, oocytes (female germ cells) have hundreds of thousands. While mature red blood cells and skins cells have few or none. More metabolically active cells such as, those found in the heart, brain, liver, kidneys, and muscles have more mitochondria. We should see then that having healthy, well-functioning mitochondria will have a powerfully positive impact on our overall health.

How the Mitochondria Produce Energy

All of our cells need a continuous supply of energy. Our mitochondria produce most of that energy through a process that involves two essential biological functions required to sustain life: breathing and eating. This process is known as oxidative phosphorylation3 (also called cellular respiration). This process is responsible for producing energy in the form of ATP. During oxidative phosphorylation, the mitochondria control a complex series of chemical reactions. This series of chemical reactions is known as the Krebs cycle and the electron transport chain. Combined, these reactions use electrons from the foods we eat and protons contained within the cycle to produce energy.

ROS, Free Radicals, and Oxidation

However, in the process a percentage of electrons will leak from the electron transport chain and form what are called reactive oxygen species (ROS).4   These molecules are very unstable, because they have acquired one or more unpaired electrons. These highly unstable and reactive atoms form potentially destructive free radicals.5 In order to neutralize their unstable electrical charge, free radicals react with other molecules in what are known as oxidation reactions. Oxidation can be thought of as “biological rusting,” as molecules steal electrons from one another it creates a new free radical, creating a snowball effect while leaving behind a trail of biological destruction.

Lipid Peroxidation

This rapid increase of free radicals within the cell degrades cell and mitochondrial membranes in yet another process, lipid peroxidation.6  This is essentially the oxidative degradation of lipids. When this happens, our cell membranes become brittle and leaky, causing them to disintegrate. And, this is not just a process that happens inside our bodies. Cooking oils that contain polyunsaturated fats are often affected by lipid peroxidation because they contain multiple double bonds that are very prone to oxidation due to especially reactive hydrogen atoms.

Free Radicals, Are Not All Bad

We must also understand that free radicals also play an important role in our health. In an optimally healthy state, they conduct very valuable roles in our bodies. They regulate many crucial cellular functions including the creation of melatonin and nitric oxide, act as natural biological signals that respond to environmental stressors (toxins and chemicals in the environment), responsible for the anticancer effects of pro-oxidative chemotherapy drugs, and play a role in the beneficial effects of exercise. So it’s not that ROS are to be avoided at all costs, which would not be possible anyhow. And it’s not that ROS in general are harmful; it’s ROS in excess that are detrimental to health.7 Our goal is to optimize amounts of ROS in our cells, not too much and not too little but just the right amounts.  Thus if we over suppress free radicals, we can run into complications. This is why if we overload or bodies with antioxidants to reduce free radicals, we can easily neutralize too many free radicals. This can lead to the suppression of important functions of free radicals. Take for example, the desirable number of ROS in cancer cell mitochondria. When free radicals build up in the cancer cell they cause the cancer cells to self-destruct via apoptosis (automatic programmed cell death).

  1. https://www.ncbi.nlm.nih.gov/books/NBK26894/
  2. http://nick-lane.net/scientific-art/
  3. https://www.ncbi.nlm.nih.gov/books/NBK21208/
  4. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3454471/
  5. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3249911/
  6. http://cdn.intechopen.com/pdfs/38477/
  7. https://file.scirp.org/pdf/ABB20120700031_37648430.pdf
  8. http://jn.nutrition.org/content/134/11/3179S.full

Fact of the week

 In the modern world there are an estimated 10,000 chemicals (food additives) commonly used in our food supply, and at least 1,000 have never been reviewed by the FDA.

In 1958 congress passed the “Food Additives Amendment.” This legislation required food manufactures to prove the safety of any food additives before they brought their product to market. But it also created a loophole. Any additive that was “generally required as safe” (GRAS) by the scientific community or was already in widespread use in food before 1958 could be added to food products without first being approved by, or even disclosed to , the FDA. It doesn’t stop there either, even foods that do not make the GRAS list are often exempt from scientific scrutiny. As the FDA allows companies to perform their own studies.

  1. https://www.nrdc.org/sites/default/files/safety-loophole-for-chemicals-in-food-report.pdf