What do wrinkles, age spots, and memory lapses have in common? These health concerns commonly appear with age and can be traced back to damaged lipid membranes in our cells and organelles. Rarely do we think about our health at the cell level, let alone our organelles, the tiny structures within our cells that perform specific and vital functions. However, the health of our cells and organelles and the elegant lipid membranes that protect them play a critical role in how we age.
Cell Membrane Damage: A “Pacemaker” for Aging
Every cell and organelle in your body is encapsulated by a biological membrane composed of orderly lipid molecules. These lipid molecules include phospholipids, which in turn, are made up of polyunsaturated fatty acids (PUFAs) such as alpha-linolenic acid (ALA), attached to a glycerol molecule and a phosphate group. Interspersed among phospholipids are additional molecules, such as proteins and cholesterol molecules. Phospholipids spontaneously self-organize to form fluent, dynamic membranes that compartmentalize the interiors of cells and organelles, separating them from the external environment. They create a barrier to the passage of molecules and ions in and out of cells, allowing cells to carefully “monitor” their environment. PUFAs help maintain the fluidity of biological membranes. Biological membranes are essential for cellular structure and physiology. (1)
Emerging research indicates that the composition of our biological membranes significantly impacts how we age. As we age, our cell and organelle membranes accumulate damage. Damage to these lipid membranes, in turn, appears to drive the aging process.
In fact, the role of membrane lipid damage in aging has been described as the “Membrane Pacemaker” theory of aging. (2)
The Membrane Pacemaker theory of aging is based on the process that occurs when delicate membrane lipids are damaged by free radicals that we encounter through food, our environment, and as byproducts of our own cellular metabolism. Free radicals are like burglars, “stealing” electrons from membrane lipids. The resulting byproducts are electron-deficient lipids and reactive, free-floating “lipid-centered free radicals.” Lipid-centered free radicals also act like burglars, pilfering electrons from other molecules, including your DNA and proteins. This process creates a vicious cycle of oxidative stress that accelerates biological aging. (3) Membrane lipid damage may thus act as a “pacemaker” in the body, running the aging process.
How Do Healthy Membranes Support Longevity?
To age well, we want to maintain healthy, resilient cell and organelle membranes. Healthy membranes support longevity through several mechanisms, including:
- Optimizing ATP production: Mitochondria are the energy “powerhouses” of our cells. The mitochondrial membrane potential is an electrochemical gradient created by protons – subatomic particles with a positive electrical charge, as they are shuttled across the inner membrane of mitochondria. This electrochemical gradient produces ATP, the body’s cellular energy “currency.” (4) Aging is characterized by a dramatic decline in mitochondrial energy production; this decline may contribute to many common complaints of aging, including fatigue, low stamina, and poor exercise tolerance.
- Supporting steroid hormone synthesis: Levels of critical steroid hormones, including estrogen, testosterone, and DHEA, steeply decline with age. Lower levels of these vital hormones are associated with age-related health impairments, including weakness, loss of muscle mass, and reduced cognitive acuity. (5, 6) Steroid hormone production begins in the endoplasmic reticulum and mitochondria; without intact ER and mitochondrial membranes, hormone synthesis suffers. Compromised lipid membranes and the associated declines in steroid hormone synthesis may thus exacerbate the aging process.
- Supporting healthy intestinal barrier function: The cells that line the intestines, called “intestinal epithelial cells,” harbor membranes rich in phospholipids. Various inflammatory triggers, including non-steroidal anti-inflammatory drugs (NSAIDs) and the Western diet, disrupt intestinal epithelial cell membranes and compromise gut health. (7, 8) Furthermore, aging is associated with declines in intestinal barrier function, opening the gut up to issues such as “leaky gut.” (9)
- Supporting healthy brain aging: As we age, the composition of the membrane lipids in our brain cells changes, adversely affecting neurotransmission. (10) These changes in neuronal membrane lipid composition may contribute to the memory lapses and loss of mental “sharpness” that we often consider inevitable consequences of aging.
- Supporting healthy skin: Cell membranes of skin cells are highly susceptible to oxidative damage through UV light exposure and contact with airborne pollutants. (11) Oxidative stress in skin plays a major role in the aging process at a level that is visible to the naked eye.
Safeguarding Biological Membranes As We Age
Below are a few essential steps we can take to support our cell and organelle membranes to optimize longevity:
- Avoid industrial seed oils. Industrial seed oils are the highly processed oils expressed from soybean, corn, canola, cottonseed, grapeseed, safflower, and sunflower seeds. These oils are very recent additions to the human diet. They are rich in polyunsaturated fatty acids (PUFAs), the same types of lipids in our cell and organelle membranes. The delicate PUFAs in industrial seed oils become damaged during the manufacturing process making them dangerous to the body from the get-go.. The consumption of industrial seed oils can trigger a chain reaction of oxidative damage inside our bodies, ultimately harming our biological membranes. By eliminating industrial seed oils from our diet and instead consuming healthy oils such as olive oil, coconut oil, and fatty cold-water fish as a source of omega-3 fatty acids, we can minimize damage to our biological membranes. (11)
- Avoid environmental toxins and detoxify your body. A variety of environmental toxins, including heavy metals and mycotoxins, can damage membrane lipids. (12, 13) Interestingly, antibiotics may also oxidatively damage the lipids in mitochondrial membranes due to the structural similarities between bacteria and mitochondria, which evolved from an ancient bacterium that took up residence inside early eukaryotic cells. (14)
- Replenish your body with quality phospholipids, essential fatty acids, and membrane antioxidants. Supplementing with high-grade phospholipids like phosphatidylcholine, and essential fatty acids (EFAs), two of the major components of biological membranes, can provide your body with the substrates needed to replace damaged lipids and mend cell and organelle membranes. Furthermore, membrane-specific antioxidants offer further support for healthy aging by fortifying cell and organelle membrane lipids against free radicals. (15) Astaxanthin is one such antioxidant that readily inserts itself in lipid membranes, providing antioxidant support. (16) Ultimately, supplementation with phospholipids and membrane-specific antioxidants may improve cellular function and promote a healthier biological aging process.
When it comes to aging well, we must consider the health of the biological membranes surrounding our cells and organelles. Our biological membranes’ health (or lack thereof) influences energy and hormone production, skin integrity, gut health, and brain function, with intersecting effects on our longevity.