Nature's Bounty Magnesium 500 mg Review: Best Budget Magnesium Supplement in 2026?

Magnesium oxide offers only 4% bioavailability — far less than glycinate or citrate forms. This means you absorb roughly 20 mg of elemental magnesium from a 500 mg tablet. If you need higher uptake for deficiency or sleep, chelated magnesium is the better choice. For example, Doctor's Best High Absorption Magnesium Glycinate delivers 200 mg of highly absorbable magnesium per two small tablets, and its lysinate glycinate chelate is designed for up to 6x better absorption. Oxide still works for baseline needs, but you may need a higher dose to achieve the same effect.

At $7.47 for 60 caplets, Nature's Bounty delivers the lowest cost per serving on the market — just 12¢. Each tablet provides 119% of the daily magnesium value, so one a day is enough for basic needs. Compare Nature Made Magnesium Oxide 400 mg Softgels at 21¢ per serving; you pay almost double for a slightly lower dose. However, because oxide absorption is low, you might need twice the dose to match a glycinate, evening out the price advantage. Still, for budget shoppers, this is the best deal.

Magnesium oxide is known to cause stomach upset more often than chelated forms. In 103,854 Amazon reviews, many users report no issues, but the most common complaint mentions diarrhea or cramping, especially when taken on an empty stomach. The coated caplet may reduce throat irritation but does not prevent GI effects. For sensitive stomachs, magnesium glycinate is an obvious upgrade — Doctor's Best users frequently note its gentleness. If you opt for Nature's Bounty, take it with food and start with half a dose if needed.

With 103,854 ratings at 4.7 stars, Nature's Bounty Magnesium is one of the most reviewed supplements on Amazon. Users praise its value, ease of swallowing, and consistent quality. However, it lacks third-party verification from USP or NSF, relying only on cGMP compliance. Pure Encapsulations Magnesium Glycinate, while pricier at $27, is tested for purity and potency — a key difference for those who prioritize quality assurance. If brand trust matters more than price, Pure Encapsulations is worth the upgrade.

CNET named Nature's Bounty Magnesium its "Best Budget" pick for 2026. However, video reviewers like Rhonda Patrick of FoundMyFitness and Dr. Janine Bowring caution that oxide is far less effective than organic salts and may even pull calcium from bones. The Rank On Top channel lists it as a solid budget basic. Overall, experts agree: if you handle oxide well and want the cheapest option, it works. For anything beyond bare-minimum supplementation, glycinate or citrate are stronger choices. This aligns with our 8.0 rating — good enough for the price, but not top-tier.