A light, science-backed guide to nutrients that support muscle maintenance, strength, and healthy aging - now with a calcium + vitamin K2 update.

Quick takeaway: Protein gets most of the spotlight, but muscles also rely on nutrients that support energy production, nerve signaling, contraction, recovery, inflammation balance, and bone-muscle crosstalk. The strongest foundation is still resistance training, adequate calories, and enough protein. WHO guidance recommends muscle-strengthening activity involving major muscle groups at least two days per week. [1]

The nutrients below are best positioned as supportive tools - not substitutes for exercise, not treatments for disease, and not replacements for a balanced diet.

1. Creatine

Helps muscles recycle quick energy for strength work.

What it does: Creatine helps regenerate ATP, the fast energy currency muscles use during short, intense efforts such as lifting, climbing stairs, or sprinting. [2]

Why it matters: Creatine does not replace training, but it may help people train with more quality and volume. When paired with resistance training, research supports benefits for lean mass and strength, including in older adults. [2, 3]

Food-first sources: Red meat and fish provide creatine. Creatine monohydrate is the most studied supplemental form.

Supplement with: Creatine Monohydrate Powder

2. Vitamin D

Supports calcium absorption, muscle function, and bone health.

What it does: Vitamin D helps the body absorb calcium and maintain calcium and phosphate levels; it also supports neuromuscular and immune function. [4]

Why it matters: Low vitamin D status can make it harder to maintain healthy bones and normal muscle function, especially in people with limited sun exposure or low intake.

Food-first sources: Fatty fish, egg yolks, fortified dairy or plant milks, and UV-exposed mushrooms. [4]

Supplement with: Vitamin D3 & K2

3. Omega-3s

EPA and DHA may support recovery and muscle quality.

What they do: EPA and DHA are long-chain omega-3 fatty acids found mainly in fish and seafood. They are components of cell membranes and are involved in inflammation-resolving pathways. [5]

Why they matter: Evidence is mixed but promising. Reviews suggest omega-3s may help preserve or improve some strength measures in older adults, especially when combined with exercise or in higher-risk groups, but results are not uniform. [6]

Food-first sources: Salmon, sardines, trout, herring, anchovies, and other oily fish. Flax, chia, and walnuts provide ALA, which converts to EPA/DHA only in small amounts. [5]

Supplement with: Omega-3 Fish Oil or Vegan Omega-3

4. HMB

A leucine metabolite studied for muscle preservation.

What it does: HMB, or beta-hydroxy-beta-methylbutyrate, is made from the amino acid leucine and is studied for its role in muscle protein balance. [7]

Why it matters: A meta-analysis in older adults with sarcopenia or frailty concluded that HMB improved lean muscle mass and helped preserve strength and function. It may be most relevant during aging, reduced activity, or recovery periods. [7]

Food-first sources: Small amounts occur naturally in foods such as avocado, citrus, and some fish; research-level intakes are typically achieved through supplementation.

5. Magnesium

A mineral muscles use to contract, relax, and make energy.

What it does: Magnesium is a cofactor in more than 300 enzyme systems, including pathways involved in protein synthesis, energy production, muscle and nerve function, blood glucose control, and blood pressure regulation. [8]

Why it matters: Muscles need magnesium for normal contraction and relaxation. Low intake or low status may contribute to fatigue, weakness, cramps, or reduced training capacity in some people.

Food-first sources: Pumpkin seeds, chia seeds, almonds, cashews, spinach, black beans, edamame, and whole grains. [8]

Supplement with: Magnesium Complex 7-in-1

6. Vitamin B12

Supports nerve-muscle communication and energy metabolism.

What it does: Vitamin B12 helps keep blood and nerve cells healthy and is involved in DNA synthesis. Deficiency can cause fatigue, anemia, numbness, tingling, and neurological changes. [9]

Why it matters: Muscle strength depends on good nerve signaling. B12 is especially important for vegans, vegetarians, older adults, and people taking medicines such as metformin or proton pump inhibitors, which can affect status. [9]

Food-first sources: Fish, meat, poultry, eggs, dairy, fortified nutritional yeast, and fortified cereals. [9]

Supplement with: Vitamin B Complex Plus

7. Calcium + Vitamin K2

Calcium supports contraction and bones; K2 helps activate proteins that guide calcium handling.

What calcium does: Calcium forms much of the structure of bones and teeth, while a small circulating pool supports muscle function, nerve transmission, blood vessel contraction and dilation, hormone secretion, and blood clotting. [10]

Where vitamin D fits: Vitamin D helps the gut absorb calcium and helps maintain calcium levels in the blood. In simple terms, vitamin D helps calcium get in. [10]

Where vitamin K2 fits: Vitamin K2 is part of the vitamin K family. Vitamin K is needed to activate vitamin K-dependent proteins, including osteocalcin in bone and matrix Gla protein (MGP) in vascular smooth muscle, bone, and cartilage. MGP is being studied because it may help reduce abnormal calcification, while osteocalcin may be involved in bone mineralization and turnover. [11]

Plain-English version: Vitamin D helps calcium enter the body; vitamin K2 helps activate proteins that support calcium going where it belongs - especially into bone-supporting pathways and away from inappropriate soft-tissue deposition. That is the precise, science-aligned way to say K2 helps keep calcium from lingering in the wrong places in the bloodstream or vessel walls. [11, 12]

What the research says: A 2023 systematic review and meta-analysis of randomized trials found vitamin K supplementation significantly lowered dp-ucMGP, a marker of poor vitamin K status, and modestly slowed progression of coronary artery calcification; the authors also noted that more rigorous trials are needed. [12]

Food-first sources: Calcium: yogurt, milk, cheese, calcium-set tofu, fortified plant milks, canned salmon or sardines with bones, kale, bok choy, and broccoli. Vitamin K2: natto, some fermented cheeses, egg yolks, and certain animal foods; MK-7 is a common supplemental K2 form. [10, 11]

Supplement with: OsteoDefence

Important K2 safety note: People taking warfarin or other vitamin K-antagonist anticoagulants should not start, stop, or change vitamin K intake without medical guidance. NIH guidance notes that people on these medicines need consistent vitamin K intakes.[11]

Simple customer-friendly guide

• Creatine: training quality and strength support.
• Vitamin D: calcium absorption, neuromuscular function, and bone support.
• Omega-3s: recovery, inflammation balance, and muscle-quality research.
• HMB: muscle protein balance during aging or reduced activity.
• Magnesium: energy production, contraction, relaxation, and nerve function.
• Vitamin B12: healthy blood cells, nerves, and muscle activation signals.
• Calcium + K2: contraction, bone structure, and calcium-handling proteins.

Bottom line

Muscle maintenance is not about one magic nutrient. It is about creating the right environment for muscle to keep building, repairing, contracting, and adapting: strength training, adequate total calories, enough protein, and supportive nutrients such as creatine, vitamin D, omega-3s, HMB, magnesium, B12, calcium, and vitamin K2.

Responsible supplement guidance

• Supplements should supplement a good diet, not replace it.
• People who are pregnant, breastfeeding, managing kidney disease, prone to high calcium levels or kidney stones, taking blood thinners, or using prescription medicines should speak with a healthcare professional before starting new supplements.
• For customer communications, avoid implying that any supplement treats or cures sarcopenia, osteoporosis, cardiovascular disease, or any other medical condition.

References

[1] World Health Organization. WHO Guidelines on Physical Activity and Sedentary Behaviour. NCBI Bookshelf. https://www.ncbi.nlm.nih.gov/books/NBK566046/

[2] Kreider RB, et al. International Society of Sports Nutrition position stand: safety and efficacy of creatine supplementation in exercise, sport, and medicine. Journal of the International Society of Sports Nutrition. 2017. https://www.tandfonline.com/doi/full/10.1186/s12970-017-0173-z

[3] Chilibeck PD, et al. Effect of creatine supplementation during resistance training on lean tissue mass and muscular strength in older adults: a meta-analysis. Open Access Journal of Sports Medicine. 2017. https://pmc.ncbi.nlm.nih.gov/articles/PMC5679696/

[4] NIH Office of Dietary Supplements. Vitamin D Fact Sheet for Health Professionals. https://ods.od.nih.gov/factsheets/VitaminD-HealthProfessional/

[5] NIH Office of Dietary Supplements. Omega-3 Fatty Acids Fact Sheet for Health Professionals. https://ods.od.nih.gov/factsheets/Omega3FattyAcids-HealthProfessional/

[6] Therdyothin A, et al. The effects of omega-3 polyunsaturated fatty acids on muscle protein synthesis in older adults: systematic review/meta-analysis. PubMed record. https://pubmed.ncbi.nlm.nih.gov/38777807/

[7] Oktaviana J, et al. The effect of beta-hydroxy-beta-methylbutyrate (HMB) on sarcopenia and frailty in older persons: a systematic review. PubMed record. https://pubmed.ncbi.nlm.nih.gov/30697623/

[8] NIH Office of Dietary Supplements. Magnesium Fact Sheet for Health Professionals. https://ods.od.nih.gov/factsheets/Magnesium-HealthProfessional/

[9] NIH Office of Dietary Supplements. Vitamin B12 Fact Sheet for Health Professionals. https://ods.od.nih.gov/factsheets/VitaminB12-HealthProfessional/

[10] NIH Office of Dietary Supplements. Calcium Fact Sheet for Health Professionals. https://ods.od.nih.gov/factsheets/Calcium-HealthProfessional/

[11] NIH Office of Dietary Supplements. Vitamin K Fact Sheet for Health Professionals. https://ods.od.nih.gov/factsheets/VitaminK-HealthProfessional/

[12] Li T, et al. Vitamin K supplementation and vascular calcification: a systematic review and meta-analysis of randomized controlled trials. Frontiers in Nutrition. 2023. https://www.frontiersin.org/journals/nutrition/articles/10.3389/fnut.2023.1115069/full