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Dr. Eric Berg DC

The Best Anti-Aging Advice I Wish I Knew in My 40's

May 14, 2026

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The Best Anti-Aging Advice I Wish I Knew in My 40's

Discover the surprising nutrient deficiency impacting 95% of adults and its link to aging. Learn why glycine is crucial for health!

A significant nutrient deficiency, often overlooked due to its classification as "non-essential," may be a primary contributor to accelerated aging and a host of health issues. This deficiency, in glycine, is prevalent across the adult population, with estimates suggesting that 95% of adults are chronically short of this vital amino acid.

Understanding Glycine's Role

Glycine, the smallest and oldest amino acid, is produced by the body. However, this endogenous production is insufficient to meet daily requirements. While the body synthesizes approximately 3 grams of glycine per day, dietary intake for most individuals ranges between 1.5 and 2 grams. This results in a daily deficit of approximately 10 grams.

The classification of glycine as "non-essential" stems from the body's ability to produce it, a criterion applied to any amino acid the body can synthesize. However, this classification fails to account for the actual physiological demand.

Dietary Sources and Modern Consumption Patterns

The primary dietary source of glycine is collagen. Historically, human ancestors consumed animals "nose to tail," ingesting significant amounts of collagen from connective tissues, skin, and cartilage. Modern dietary habits, however, have shifted towards consuming more tender cuts of meat, which contain minimal collagen. For instance, an average tender steak comprises only 1-3% collagen. This dietary shift means that despite collagen constituting 30% of the body's protein, its dietary intake is severely limited.

Even individuals following a carnivore diet, primarily consuming steak, can be deficient in glycine if they do not incorporate organ meats or other collagen-rich animal parts. Vegans, children, and older adults are also identified as groups at high risk for glycine deficiency.

The Triage System and Glycine Allocation

The body employs a triage system for nutrient allocation, prioritizing essential survival functions. Glycine is directed first to critical processes such as:

  • Red Blood Cell Production: Glycine is a key component in the synthesis of heme, the protein responsible for oxygen transport in red blood cells. Without sufficient heme, oxygen transport is compromised, posing an immediate survival threat.
  • DNA and RNA Synthesis: These genetic blueprints are crucial for cellular reproduction and the continuation of life.

When glycine levels are insufficient, the body conserves it for these paramount functions, leaving other vital processes under-resourced.

Glycine's Impact on Various Bodily Functions

Beyond immediate survival needs, glycine plays a crucial role in numerous bodily functions, and its deficiency can manifest in various health problems:

  • Bile Salt Production: Glycine is essential for the synthesis of bile salts, which aid in fat digestion and the absorption of fat-soluble vitamins (A, D, E, K) and omega-3 fatty acids. Bile salts also help prevent small intestinal bacterial overgrowth (SIBO).
  • Glutathione Synthesis: Glycine is a precursor to glutathione, the liver's primary antioxidant responsible for detoxifying the body from toxins, alcohol, and processed foods. Insufficient glycine can impair detoxification pathways, affecting an individual's capacity to handle environmental poisons.
  • Neurotransmitter Function (GABA): Glycine is a precursor to Gamma-Aminobutyric Acid (GABA), a neurotransmitter that acts as a natural sedative, promoting relaxation and sleep. Low glycine levels can contribute to insomnia, anxiety, nervousness, and hyperactivity, particularly in children.
  • Immune System Function: Glycine is vital for immune cells, specifically macrophages. When macrophages die, they release glycine to signal the cessation of inflammation. A deficiency can lead to unresolved inflammation.
  • Skin Health: Glycine is a building block for collagen, essential for skin elasticity and preventing premature aging.
  • Connective Tissues: Adequate glycine is necessary for the integrity of fascia, tendons, cartilage, ligaments, and bones. Deficiency can lead to loss of body shape, sagging, increased susceptibility to tendon injuries, joint degeneration, and bone fragility.
  • Arterial Health: Collagen, rich in glycine, forms the structure of arteries. Insufficient glycine can contribute to arterial problems such as high blood pressure and blockages.
  • Gut Lining Integrity: Glycine supports the health of the gut lining, making bone broth and collagen beneficial for healing conditions like leaky gut.
  • Hair and Nails: Glycine is also required for the health of hair and nails.

Addressing Glycine Deficiency

While the speaker does not recommend specific glycine supplements, they advocate for increasing collagen intake through food sources. High-quality collagen powders, consumed with Vitamin C (a necessary cofactor for collagen synthesis), are suggested as a dietary supplement.

The speaker also references a free 2-minute quiz designed to identify imbalances in key bodily signals, including those potentially linked to nutrient deficiencies.

Introduction to Glycine Deficiency

The core problem identified is a widespread deficiency in glycine, an amino acid crucial for health, despite its 'non-essential' classification. Modern diets fail to provide adequate amounts, leading to a significant daily deficit.

  • The speaker, 61, shares anti-aging advice missed in her 40s.
  • The issue is not diet (starch, sugar, seed oil) or exercise, but a nutrient deficiency.
  • This nutrient is classified as 'non-essential' but is vital.
  • Recommended daily intake is ~15g; body produces 3g; diet provides 1.5-2g, leaving a 10g deficit.
  • The nutrient is Glycine, an amino acid the body makes, hence 'non-essential'.

Sources of Glycine and Modern Diet Issues

The shift from 'nose-to-tail' eating to consuming only tender muscle meats has drastically reduced collagen intake. Since collagen is the primary dietary source of glycine, this dietary change leads to a deficiency.

  • Most dietary glycine comes from collagen, not typically from meat, eggs, or fish.
  • Ancestors consumed animals 'nose to tail', including collagen-rich parts.
  • Modern diets favor tender meats with very low collagen content (1-3%).
  • Collagen constitutes 30% of body protein, yet we are not getting enough.
  • Glycine is the smallest and oldest amino acid (3.8 billion years).

Glycine's Role in Bodily Functions (Triage)

The body prioritizes glycine for critical survival functions like red blood cell production and DNA/RNA synthesis. When deficient, less vital functions suffer, impacting overall well-being and signaling pathways.

  • The body 'triages' nutrients, prioritizing survival functions.
  • Glycine is essential for building heme, a key component of red blood cells for oxygen transport.
  • It's also vital for DNA and RNA synthesis, crucial for cell reproduction.
  • A toxic internal environment (like a polluted fish tank) hinders overall health.
  • Body signals like insulin, cortisol, inflammation, sleep, and gut function are affected by nutrient availability.

Glycine's Impact on Bile Salts, Detoxification, and Sleep

Glycine deficiency impairs fat digestion and nutrient absorption via bile salts, hinders detoxification through reduced glutathione production, and disrupts sleep and relaxation due to insufficient GABA.

  • Glycine is necessary for producing bile salts, which aid fat breakdown and absorption of fat-soluble vitamins (A, D, E, K, omega-3s).
  • Adequate bile salts prevent small intestinal bacterial overgrowth (SIBO).
  • Glycine is required to synthesize glutathione, the liver's primary antioxidant for detoxifying toxins (from food, alcohol, etc.).
  • Glycine is a precursor to GABA, a neurotransmitter that acts as the nervous system's 'brake', promoting sleep and relaxation.
  • Low GABA levels, linked to glycine deficiency, can cause insomnia, anxiety, and hyperactivity in children.

Glycine and the Immune System, Skin, and Joints

Glycine is critical for immune function, regulating inflammation, and maintaining the structural integrity of skin, fascia, tendons, cartilage, and bones. Deficiency leads to premature aging, increased injury risk, and joint problems.

  • The immune system, particularly macrophages (front-line defense cells), depends on glycine.
  • Glycine helps turn off the inflammatory switch after macrophage activity.
  • Insufficient glycine can lead to chronic inflammation and reliance on medication.
  • Skin aging is accelerated when glycine is scarce, as collagen production decreases.
  • Fascia, tendons, cartilage, and bones (which are largely collagen) are weakened, leading to injuries, sagging, and joint degeneration.

Personal Experience and Broader Health Implications

The speaker's personal health struggles highlight the pervasive impact of glycine deficiency. Beyond structural tissues, it affects arteries, gut lining, ligaments, hair, and nails, underscoring its systemic importance.

  • The speaker experienced severe fragility, fractures, inflammation, arthritis, and sleep issues in youth due to a junk food diet and glycine deficiency.
  • Arteries are largely composed of collagen, making glycine crucial for arterial health (preventing high blood pressure and clogging).
  • The gut lining requires glycine, making bone broth and collagen beneficial for healing leaky gut.
  • Ligaments, connecting bone to bone, also need glycine for strength and stability.
  • Glycine is needed for hair and nail health.

Dietary Recommendations and Conclusion

The key takeaway is that modern dietary habits, lacking nose-to-tail consumption, lead to a significant glycine deficiency. Increasing collagen intake, ideally with Vitamin C, is recommended to address this widespread issue.

  • Modern diets, including carnivore diets focused solely on steak, often lack sufficient glycine.
  • Vegans, children, and older adults are particularly at risk of deficiency.
  • The speaker recommends increasing collagen intake from food sources or high-quality collagen powder.
  • Vitamin C is a crucial co-factor for collagen synthesis and effectiveness.
  • The modern diet's lack of nose-to-tail consumption is the root cause of widespread glycine deficiency.