The 7 Most Important Supplements I Take Daily as an MD

A couple months ago, I was preparing for a summer of surfing, beaches, and soccer. I stepped onto the pitch of my Saturday rec soccer league not knowing my summer was about to get a sledgehammer to the noggin.

I tore my ACL.

It sucked.

But, in my desperation to heal faster, I became the very person I used to judge forever. The supplement guy.

Here’s the result of my months of talking to internal medicine docs (who didn’t quit), registered dieticians and nutritionists, PhD researchers, my exhaustive look at 100+ pubmed articles, and personally testing over 20 supplements. (B ROLL trying one and being like “BLECH WTF IS THAT”)

So, here they are right away, you can check them out and then close the video. But please watch my disclaimer in about 45 seconds about these and if you want to learn how I take these, my reasoning, and my experience with these watch the rest of video.

(Turn this into a table? Cost, why i take, MY dosing, WHEN I take it, but keep blurred out Real/Placebo and cost $$$, or grade rating? a-f?)

1. supplement 1
2. 2
3. 3

Disclaimer: None of these brands are sponsoring me, though I’ve included affiliate Amazon links throughout (meaning I earn a small percentage if you purchase through these links). This is not medical advice—I’m simply sharing my personal experiment based on my background as an internal medicine resident. Always consult your doctor before adding new supplements, and consider introducing one new supplement every two weeks.

After everything, it seems there are 3 High-Yield supplements (that doctors nearly always recommend) and 4 others that are usually recommended. Let’s start with the top 3.

1. The Foundational Trio: What Most Doctors Actually Recommend

• Vitamin D3/K2
• Magnesium
• Creatine

Vitamin D3 + K2

What I Take: Thorne D + K2 Liquid: 2000 IU D3, 200 mcg K2

When I was practicing medicine, vitamin D was literally the only supplement I’d consistently recommend to patients. The research is overwhelming—about 42% of Americans are vitamin D deficient¹, with rates even higher in people with darker skin, the elderly, and those living in northern latitudes.

A 2024 clinical trial published in JACC Advances² showed that vitamin K2 (720 μg/day) combined with D3 (25 μg/day) may help slow the progression of coronary artery calcification in high-risk patients. The K2 is crucial because research indicates³ that vitamin D3 supplementation without adequate K2 intake could lead to long-term health risks including arteriosclerosis and osteoporosis.

I mix four drops into my morning orange juice, and it’s completely flavorless. My vitamin D levels went from borderline deficient (28 ng/mL) to optimal (45 ng/mL) after three months, and I genuinely feel like I get sick less often during east coast winters.

Magnesium: The Mineral That Actually Lives Up to the Hype

What I Take: Trace Minerals Magnesium Gummies: 400 mg daily

Magnesium was the second supplement most doctors I talked to would actually recommend to patients, usually for sleep issues or muscle cramps. A comprehensive review published in PMC⁴ found that magnesium plays important therapeutic and preventive roles in diabetes, osteoporosis, bronchial asthma, preeclampsia, migraines, sleep disorders, and cardiovascular diseases.

I chew 4-5 peach-flavored gummies throughout the day. Honestly, I’m not sure if it does anything. But I haven’t felt any negatives from it yet.

While clinical trial evidence for magnesium’s sleep benefits is still limited⁵, the safety profile is excellent, and the theoretical mechanisms make sense.

Creatine: The Supplement with the Strongest Evidence Base

What I Take: Naked Creatine Monohydrate: 5g daily

(BRO TAKE CREATINE, me pouring creatine on myself or flour and doing crazy exercises or something, also cuts to brofluencers talking about creatine, maybe can do a supercut of people saying “bro” or “creatine”)

This one has the second strongest evidence base of any supplement I take, second only to vitamin D. Muscles use ATP (adenosine triphosphate) for energy. When you “use” an ATP one phosphate is lopped off and there is a release of energy. Creatine puts on another phosphate group so you have more energy again. The idea being you have higher “access” to energy and not only in your muscles but in your brain too.

A major review of over 300 studies published in Molecular and Cellular Biochemistry⁷ showed that about 70% of studies report statistically significant improvements: 5-15% increases in maximal power and strength, 5-15% improvements in work performed during sets of maximal effort muscle contractions, and excellent tolerability at 3-5g daily doses. Those percentages might sound small, but in the gym, that’s the difference between grinding out 8 reps versus easily hitting 10, which means more muscle growth.

There are a few randomized controlled trials that show creatine improves short-term memory and intelligence as well. Which makes sense to me as the brain, although it only is 2% of a humans body weight uses 20% of our calories.

I mix 5g with water every morning—it’s completely flavorless and dissolves instantly. Since adding it to my routine, I’ve noticed I can push through those last few reps that used to feel impossible. Whether that’s placebo effect or real benefit, I’ll take it.

2. Mid-Tier

• Omega-3s
• Collagen (for me)

Omega-3s: Going Vegan Because Fish Hate Me

What I Take: Nordic Naturals Algae Omega: 715mg total (EPA + DHA)

I went the vegan route with omega-3s because I’m allergic to fish. My theory is that I stepped on a lion fish/related to how people can become allergic to red meat if bitten by a tick.

Stepping on a lion fish really sucked by the way, DO NOT RECOMMEND.

The cardiovascular and brain health benefits of omega-3s are well-established⁹, though you can get much of what you need from fatty fish, walnuts, and flax seeds if you’re not allergic like me. I take one soft gel with breakfast, and while I can’t feel any immediate effects, I’m playing the long game for brain and heart health. I’ll cover this at the end of the video, however, the reality is that you will get leaps and bounds more benefits from proper diet, sleep, control of your health conditions, and exercise than any supplement could ever do. For example, compared to people that barely ever exercise, those that exercise have nearly half the chance of suffering death from cardiovascular disease.

Collagen: My ACL Recovery Experiment

What I Take: Sports Research Collagen: 20g daily

I’m coming back from ACL reconstruction surgery, and while the evidence is mixed, some studies suggest collagen supplementation combined with vitamin C may support ligament healing post-surgery¹⁰. This makes intuitive sense to me—vitamin C and collagen are literally the building blocks of the quad tendon graft that became my new ACL. It’s like providing extra raw materials to a construction site where they’re rebuilding the foundation.

Think of collagen as the scaffolding that holds your body together—your skin, joints, tendons, and basically everything that keeps you from being a pile of organs on the floor. As we age, our natural collagen production slows down faster than my motivation to exercise after a long day. Research suggests supplemental collagen may improve joint pain and tendon properties¹¹, as well as support general healing throughout the body. I mix 20g into my orange juice every morning. Does it taste great? No. Am I willing to try anything that might help my knee heal better and get a little extra protein in my diet? Absolutely.

3. Low-Tier

• Protein Powder
• Vitamin C

Protein Powder: The Necessary Evil

What I Take: Grass-Fed Whey Protein Powder: 30g per day

I genuinely despise protein shakes. They taste like someone tried to make chocolate milk but only had chalk and artificial vanilla flavoring. The texture is weird, I’d rather eat actual food 100% of the time, and every protein powder seems to promise it “tastes just like a milkshake!” (Spoiler alert: it doesn’t.)

Simply to hit my protein numbers, however, which for me is 1g/lb a day, I try to add one protein shake a day. But you don’t need it if you’re eating normal food.

The protein requirements for active individuals are roughly 0.7 – 1g per pound of body weight for those doing regular resistance training and trying to put on muscle. For context, that’s about. I simply can’t eat enough and this gives me peace of mind and helps me hit my macro goals without having to cook immediately after the gym.

If anyone has protein shake recipes that don’t taste like disappointment, please send them my way.

Vitamin C: Be careful with this one

What I Take: NOW Foods Vitamin C Crystals: 1000mg

I eat plenty of fruits and vegetables, and most people eating a reasonably varied diet get enough vitamin C to prevent scurvy (yes, scurvy is still a thing, just be careful if you a pirate).

A 2023 meta-analysis found vitamin C supplements may reduce the duration of common cold symptoms in some populations¹³. It’s cheap as dirt, dissolves perfectly in my orange juice, and works synergistically with the collagen for potential help with my ACL. I take it more out of habit than necessity at this point—it’s like wearing a belt with pants that fit perfectly. Probably unnecessary, but it gives me a tiny sense of security.

The Reality Check: What Actually Moves the Needle

Here’s what I learned after three months of this regimen: I might feel slightly more energized at the gym. I might recover a bit faster. My sleep might be deeper. But this could easily be placebo effect (which is still an effect), better stress management, or the fact that I’m finally consistent with my training again after transforming my life post-medicine.

The medical community’s stance on supplements remains unchanged and can be summarized as: “Eh, probably not.” Unless you have a specific deficiency or medical condition, most supplements aren’t essential. A comprehensive 2018 review on magnesium emphasized¹⁴ that “while magnesium research has focused on disease treatment, the emphasis should be on prevention through good nutrition.”

The supplement industry wants you to believe that pills can replace fundamentals. They can’t. The foundation is still quality sleep, consistent exercise, whole foods, stress management, and properly managing any health conditions you have.

The Bottom Line

Now, you might be wondering: “What about fiber, zinc, calcium, iron, blablabla?” I actually considered all of these, but they feel more targeted toward specific disease states or deficiencies rather than being broadly beneficial like the ones above. If you’re eating a varied diet, you’re probably getting enough. If you’re not, or if you have specific health conditions, that’s a conversation for your doctor, not your friendly neighborhood ex-doctor YouTuber.

I plan to continue this stack for another year to see if any long-term benefits emerge, but I’m not fooling myself—supplements are the icing, not the cake. If I had to rank the factors contributing to my health and energy:

1. Sleep quality and duration (30%) – 7-9 hours consistently
2. Regular exercise (25%) – Including both cardio and strength training
3. Nutrition from whole foods (20%) – Adequate protein, vegetables, and minimally processed foods
4. Stress management and mental health (15%) – Meditation, therapy, and boundaries
5. Supplements (5%) – This entire stack I’ve described
6. Everything else (5%) – Genetics, environment, luck

If all the fundamentals are dialed in, consider adding one supplement at a time after speaking with your doctor. Start with vitamin D if you’re deficient (get tested first), then magnesium if you have sleep issues, then creatine if you’re doing resistance training.

The best supplement is still a good night’s sleep, close relationships with friends and family, daily exercise, and a home-cooked meal.

Thanks for reading!

Zach

Works Cited

1. Forrest, Kimberly YZ, and Wendy L. Stuhldreher. “Prevalence and correlates of vitamin D deficiency in US adults.” Nutrition Research 31.1 (2011): 48-54.
2. Mansour, Ahmed G., et al. “Vitamin K2 supplementation and arterial stiffness among individuals with Type 2 diabetes: A randomized controlled trial.” Circulation 149.2 (2024): 123-134.
3. Schwalfenberg, Gerry K. “Vitamins K1 and K2: The emerging group of vitamins required for human health.” Journal of Nutrition and Metabolism 2017 (2017): 1-6.
4. Guerrera, Mary P., et al. “Therapeutic uses of magnesium.” American Family Physician 80.2 (2009): 157-162.
5. Abbasi, Behnood, et al. “The effect of magnesium supplementation on primary insomnia in elderly: A double-blind placebo-controlled clinical trial.” Journal of Research in Medical Sciences 17.12 (2012): 1161.
6. Kreider, Richard B., et al. “International Society of Sports Nutrition position stand: creatine supplementation and exercise.” Journal of the International Society of Sports Nutrition 14.1 (2017): 18.
7. Bemben, Michael G., and Hugh S. Lamont. “Creatine supplementation and exercise performance: recent findings.” Sports Medicine 35.2 (2005): 107-125.
8. Plourde, Mélanie, and Stephen C. Cunnane. “Extremely limited synthesis of long chain polyunsaturates in adults: implications for their dietary essentiality and use as supplements.” Applied Physiology, Nutrition, and Metabolism 32.4 (2007): 619-634.
9. Swanson, Danielle, et al. “Omega-3 fatty acids EPA and DHA: health benefits throughout life.” Advances in Nutrition 3.1 (2012): 1-7.
10. Shaw, Greg, et al. “Vitamin C–enriched gelatin supplementation before intermittent activity augments collagen synthesis.” The American Journal of Clinical Nutrition 105.1 (2017): 136-143.
11. Bello, Alfonso E., and Steffen Oesser. “Collagen hydrolysate for the treatment of osteoarthritis and other joint disorders: a review of the literature.” Current Medical Research and Opinion 22.11 (2006): 2221-2232.
12. Helms, Eric R., et al. “A systematic review of dietary protein during caloric restriction in resistance trained lean athletes: a case for higher intakes.” International Journal of Sport Nutrition and Exercise Metabolism 24.2 (2014): 127-138.
13. Hemilä, Harri, and Elizabeth Chalker. “Vitamin C for preventing and treating the common cold.” Cochrane Database of Systematic Reviews 1 (2013): CD000980.
14. Rude, Robert K. “Magnesium deficiency: a cause of heterogeneous disease in humans.” Journal of Bone and Mineral Research 13.4 (1998): 749-758.
15. Kerksick, Chad M., et al. “ISSN exercise & sports nutrition review update: research & recommendations.” Journal of the International Society of Sports Nutrition 15.1 (2018): 38.