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The High Performance Journal - March 25th, 2025

Over the past year, I’ve been secretly experimenting with myself—think biohacking, but with less hype and more data.

I tested five under-the-radar supplements, and the results? More energy, faster recovery, and noticeable upgrades in how I move, feel, and perform.

Now, full transparency: You don’t need supplements to be healthy.

But the right ones can give you the right edge—kind of like putting premium fuel in a high-performance car.

So today, let's take a dig into five underrated supplements you might not be taking—but should consider.

You ready? Let's go 🔥

🚨 Important Dan Note: Supplements are there to "supplement" your diet—not to replace the fact that you haven’t eaten a vegetable since college. The smart move? Find out what you’re deficient in, and then fill in the gaps (preferably with food first, pills second).

Also: everything I recommend, I’ve tried myself. N=1, but I’m a very persuasive sample size. 

5 Underrated Health Supplements You're Probably Not Taking

Supplement #1 - Glycine

The Swiss Army knife of amino acids.

Benefits:

• Improves sleep by cooling the body and calming the mind.
• Reduces inflammation.
• Supports joint and collagen health.
• Boosts cognitive function.

Who Should Use It:

• Individuals with Sleep Issues: Those struggling with insomnia or poor sleep quality.
• Athletes: For joint support and recovery.
• People Seeking Anti-Inflammatory Benefits: Anyone looking to reduce inflammation.

Why I Use It:

I've been max dosing this supplement and the improvements it's made to my sleep have been a chef's kiss. Paired with creatine, and my recovery feels next-level. Glycine is criminally underrated for how much it helps across the board.

Supplement #2 - Berberine 

Nature’s version of metformin—with a side of appetite control.

Benefits:

• Regulates blood sugar and insulin.
• Aids in weight loss by improving metabolic function.
• Lowers cholesterol and blood pressure.
• Supports gut health.

Who Should Use It:

• Individuals with Diabetes or Pre-Diabetes: For blood sugar management.
• Those Seeking Weight Loss: Supports metabolic health.
• People Concerned About Cardiovascular Health: Anyone looking to improve heart health.

Why I Use It:

After cutting down to 15% body fat, I found my HbA1c (a long-term blood sugar marker) was still too high. Enter Berberine. It helped bring things back to normal—and something I've noticed is that it curbs appetite, too.

Supplement #3 - Collagen Peptides

 For smoother skin, stronger joints, and bones that don’t creak.

Benefits:

• Improves skin elasticity and hydration.
• Strengthens joints and cartilage.
• Supports bone density.
• Aids in muscle recovery.

Who Should Use Them:

• Athletes and Fitness Enthusiasts: For muscle recovery and joint support.
• Individuals with Skin Concerns: Those experiencing aging skin or seeking improved skin health.
• People with Joint Issues: Anyone dealing with joint pain or arthritis.

Why I Use It:

No offense, but I want my skin to age like ​Paul Rudd and not that guy from Cocoon​. Collagen gives me that, plus joint support and a protein bump. It’s vanity and performance—my favorite combo.

Supplement #4 - Myo-inositol

Insulin sensitivity’s best friend.

Benefits:

• Improves metabolic health.
• Reduces anxiety and depression.
• Supports hormone balance in women (especially with PCOS).
• May enhance fertility.

Who Should Use It:

• Individuals with Metabolic Issues: Those seeking to improve insulin sensitivity.
• Women with PCOS: For managing symptoms and improving fertility.
• People with Anxiety or Depression: May benefit from its mental health effects.

Why I Use It:

My slightly elevated HbA1c suggested I might have some insulin resistance going on. Myo-inositol helps with that, and as a surprise bonus, it supports mental clarity and calm. Also a big win for women with PCOS.

Supplement #5 - L-Theanine

Like a chill pill for your coffee buzz.

Benefits:

• Reduces stress and anxiety.
• May improve sleep quality.
• Enhances focus and mental clarity—especially with caffeine.
• Helps manage blood pressure.

Who Should Take It:

• Individuals with Anxiety or Stress: Those seeking natural stress relief and anxiety management.
• People with Sleep Issues: Individuals experiencing difficulty falling asleep or staying asleep.
• Students or Professionals: Anyone looking to improve focus and cognitive performance.
• Those with High Blood Pressure: Individuals seeking natural ways to manage blood pressure.

Why I Use It:

I pair L-theanine with my morning coffee and feel like I’ve unlocked Jedi focus. It smooths out the caffeine jitters and leaves me calm, alert, and weirdly more productive.

Are You Taking Any Of These?

These supplements aren’t for everyone. Your body, your rules. But if you're looking for that extra 10%—better sleep, sharper focus, smoother recovery—these five might deliver.

Try one at a time. Track how you feel. Be ruthless with what works—and what doesn’t.

Because the truth is, while health isn't about taking more, it’s about taking what works.

Onward and upward. 🚀

- Dan

When you're ready, here are 3 ways I can help:

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References

1. Kviatkovsky, S. A. (2022). Collagen peptide supplementation for pain and function. Journal of Orthopaedic Research, 40(5), 1031–1038. doi: 10.1002/jor.25141 - Kumar, S. (2015).
2. A double-blind, placebo-controlled, randomized, clinical trial to evaluate the effectiveness of collagen peptide on osteoarthritis. Journal of the Science of Food and Agriculture, 95(8), 1815–1822. doi: 10.1002/jsfa.6922 - Clifford, T. (2019).
3. The effects of collagen peptides on muscle damage, inflammation, and bone turnover following exercise: a randomized controlled trial. Amino Acids, 51(6), 829–839. doi: 10.1007/s00726-019-02733-4 - Costantino, D. (2009).
4. Metabolic and hormonal effects of myo-inositol in women with polycystic ovary syndrome: a double-blind trial. European Review for Medical and Pharmacological Sciences, 13(2), 105–110. - Mellonie, P. (2024).
5. The Effectiveness of Myo-Inositol in Women With Polycystic Ovary Syndrome. Journal of Clinical and Diagnostic Research, 18(2), OE01–OE04. doi: 10.7860/JCDR/2024/55545.5624 - Vadnal, R. (1998).
6. Initial clinical studies have shown that myo-inositol has psychoactive effects, and is effective in the treatment of specific mood and anxiety disorders. Journal of Clinical Psychopharmacology, 18(5), 429–432. doi: 10.1097/00004714-199810000-00010 - Zhong, Z. (2003).
7. Bischof, K., Stafilidis, S., Bundschuh, L., Oesser, S., Baca, A., & König, D. (2023). Influence of specific collagen peptides and 12-week concurrent training on recovery-related biomechanical characteristics following exercise-induced muscle damage—A randomized controlled trial. Frontiers in Nutrition, 10. ​https://doi.org/10.3389/fnut.2023.1266056​.
8. L-Glycine: a novel anti-inflammatory, immunomodulatory, and cytoprotective agent. Current Opinion in Clinical Nutrition and Metabolic Care, 6(2), 229–240. doi: 10.1097/00075197-200303000-00013 - Ullah, R. (2020).
9. Glycine, the smallest amino acid, confers neuroprotection against D-galactose-induced neurodegeneration and memory impairment by regulating the c-Jun N-terminal kinase signaling pathway. Aging, 12(11), 10133–10150. doi: 10.18632/aging.103245
10. Cao, Changwei & Xiao, Zhichao & Ge, Changrong & Wu, Yinglong. (2021). Animal by-products collagen and derived peptide, as important components of innovative sustainable food systems—a comprehensive review. Critical Reviews in Food Science and Nutrition. 62. 1-25. 10.1080/10408398.2021.1931807.
11. Utami AR, Maksum IP, Deawati Y. Berberine and Its Study as an Antidiabetic Compound. Biology (Basel). 2023 Jul 8;12(7):973. doi: 10.3390/biology12070973. PMID: 37508403; PMCID: PMC10376565.
12. Williams, J. L. (2020). The Effects of Green Tea Amino Acid L-Theanine on Stress Responses and Anxiety Levels in Human Randomised Controlled Trials. Nutrients, 12(22), 5593. doi: 10.3390/nu12225593
13. Kim, J. (2019). Psychotropic effects of L-theanine and its clinical properties. Pharmacological Research, 146, 104254. doi: 10.1016/j.phrs.2019.104254
14. Baba, Y. (2021). Effects of l-Theanine on Cognitive Function in Middle-Aged and Older Adults. Nutrients, 13(8), 2511. doi: 10.3390/nu1308251
15. https://www.frontiersin.org/journals/nutrition/articles/10.3389/fnut.2022.853846/full#conf1​ 
16. Marine L. Croze, Christophe O. Soulage, Potential role and therapeutic interests of myo-inositol in metabolic diseases, Biochimie, Volume 95, Issue 10,2013, Pages 1811-1827, ISSN 0300-9084 https://doi.org/10.1016/j.biochi.2013.05.011.​ 
17. Yin J, Xing H, Ye J. Efficacy of berberine in patients with type 2 diabetes mellitus. Metabolism. 2008 May;57(5):712-7. doi: 10.1016/j.metabol.2008.01.013. PMID: 18442638; PMCID: PMC2410097.