AlgaeCal Plus is a plant-based calcium supplement made from a unique South American marine algae called Mesophyllum superpositum. These USDA-certified organic algae are sustainably hand-harvested from the ocean, gently sun-dried, and milled into a fine powder.

Unlike traditional calcium supplements, which are typically derived from rocks like limestone or marble, AlgaeCal Plus is a whole-food source of all 13 essential bone-supporting minerals: calcium, magnesium, manganese, phosphorous, nickel, silica, copper, vanadium, potassium, zinc, boron, selenium and strontium. And because it comes from a living plant, this natural mineral matrix is easier for your body to absorb and utilize. 

In addition to these 13 minerals we also add full clinical doses of vitamins C, D, and K. 

Clinical research published in three peer-reviewed scientific journals shows that the 16 nutrients in AlgaeCal Plus don’t just slow bone loss; they can actually help increase bone density in adults. No other calcium supplement can make this claim. Because AlgaeCal is the ONLY one that’s clinically supported to increase bone density. 

To maximize your bone-building, take 4 capsules of AlgaeCal Plus a day. (This was the dosage that led to the most significant bone density increases in clinical trials).

We recommend splitting the daily 4 capsule dose into 2 servings of 2 capsules throughout the day. Your body can only absorb 500mg of calcium at a time, so taking more than 2 AlgaeCal capsules in one serving would lead to unabsorbed calcium.

And finally, it’s best to take your AlgaeCal Plus with food. That’s because taking calcium with food increases how well you absorb it. When you eat, your stomach produces acid that dissolves the minerals in AlgaeCal Plus so they can be properly absorbed when they reach your intestinal tract.

For more information on scheduling your AlgaeCal supplements with meals –– and any prescription medication or supplements you’re currently taking –– click here.

AlgaeCal Plus contains 16 nutrients clinically supported to increase bone density.

In fact, AlgaeCal is the only calcium supplement in the world with human clinical studies showing actual increases in bone density—not just a slowdown in bone loss.

These nutrients work together to build new bone and protect the bone you already have:

Plant-Based Minerals (from the USDA-certified organic Mesophyllum superpositum.)

- Calcium – the main structural mineral that gives bones their strength and hardness.

- Magnesium – activates vitamin D and supports the formation of new bone tissue.

- Boron – enhances absorption of calcium and magnesium and helps regulate bone-protective hormones.

- Zinc – essential for collagen synthesis and bone tissue repair.

- Copper – works with zinc to create strong collagen cross-links for flexible, resilient bones.

- Manganese – aids the production of bone cartilage and connective tissue.

- Selenium – powerful antioxidant that protects bone cells from oxidative stress.

- Strontium – naturally occurring trace mineral that supports bone formation and slows bone breakdown.

- Silica (Silicon) – helps initiate bone mineralization and supports collagen production.

- Vanadium – assists enzymes involved in bone growth and mineral metabolism.

- Nickel – required in tiny amounts for enzymes that support bone and cartilage formation.

- Phosphorus – partners with calcium to form the mineral crystals that harden bone.

- Potassium – helps neutralize excess acids in the body that can draw minerals out of bones.

Added Bone-Building Co-Factors

- Vitamin D3 – enhances calcium and magnesium absorption so minerals reach your bones.

- Vitamin K2 (MK-7) – directs calcium into bone and keeps it out of arteries.

- Vitamin C – stimulates collagen production, creating the flexible framework where minerals attach.

AlgaeCal Plus is dairy-free, soy-free, gluten-free, non-GMO, and contains only naturally occurring trace minerals—no synthetic fillers or artificial additives. While we don’t third-party test for these allergens, none are added during manufacturing.

You don’t have to, but if you’re dealing with bone loss, taking AlgaeCal Plus together with Strontium Boost delivers the fastest results.

Clinical studies show:

- AlgaeCal Plus alone can increase bone density by an average of 1.3% per year.

- AlgaeCal Plus + Strontium Boost together produce an average 3% increase in just one year. And most people see results within the first 6 months. 

So when you add Strontium Boost to your AlgaeCal Plus you’re going to build bone faster. That’s right. You’ll build more bone in less time.

And when you take both products together, you’re also covered by our Stronger Bones For Life Guarantee. So when you take AlgaeCal Plus and Strontium Boost, as directed, you’re guaranteed to see measurable bone density increases within six months – or your money back! 

See reviews from people who’ve successfully used AlgaeCal Plus & Strontium Boost here. 

Each serving of AlgaeCal Plus provides 360 mg of elemental calcium in two capsules. That’s 720 mg per day when you take the full four-capsule daily dose.

This is the exact amount used in clinical studies that showed measurable increases in bone mineral density.

You don’t need more calcium, you need the right kind of calcium. Unlike ordinary rock-based calcium (from limestone or marble), AlgaeCal Plus delivers plant-based, whole-food calcium with 12 essential bone-building minerals + vitamins C,D,& K. These 16 nutrients are easy for your body to absorb and—most importantly—are clinically supported to increase bone density, something other calcium supplements simply can’t do.

AlgaeCal Plus comes in size zero soft vegetarian capsules which are easy to swallow.

However, if swallowing capsules is difficult, you can gently pull them apart and sprinkle the tasteless powder into food or drinks. Semi-solid foods such as smoothies, applesauce, or yogurt work best.

Avoid mixing the powder into hot liquids above 120°F (49°C), as high temperatures can reduce the potency of vitamins C, D, and K2.

Because the powder contains a wide range of natural minerals, it is only partially water-soluble, so it won’t completely dissolve in liquid.

No. AlgaeCal Plus is safe and without adverse side effects. Here’s why:

- Plant-based, not rock-based: Unlike traditional calcium supplements made from limestone or marble, AlgaeCal Plus is a food-source calcium similar to the calcium found in vegetables like broccoli and kale. So your body recognizes it as food and absorbs it accordingly.

- Balanced with co-factors: Each serving provides additional magnesium, boron, vitamin K2, and vitamin D3. These nutrients work together to move calcium into your bones where it belongs, and away from soft tissues like arteries, kidneys, or eyes.

- Clinically effective at a lower dose: AlgaeCal Plus increases bone density with only 720 mg of calcium per day, the exact amount used in human clinical studies. Traditional calcium supplements often recommend 1,200 mg or more—and still only slow bone loss.

Because AlgaeCal Plus delivers the right kind of calcium, in the right balance, it strengthens bones without the risks of kidney stones or arterial calcification.

No. AlgaeCal Plus is gentle on the stomach. The digestive discomfort many people experience with regular calcium supplements comes from their rock-based source (limestone or marble), which the human body struggles to break down.

AlgaeCal Plus is different. It provides plant-based calcium naturally balanced with magnesium and other supportive minerals, making it easy to digest and absorb, without the constipation, gas, or bloating common to traditional calcium.

For best results, split your daily dose: take two capsules with breakfast and two with dinner. Taking AlgaeCal Plus with food further improves absorption and helps keep your digestive system comfortable.

Yes. Even if you’re small-framed, your bones require the same essential nutrients to stay strong.

In fact, being petite can actually increase your risk of bone loss because you start with less skeletal mass. So giving your body the full daily dose of AlgaeCal Plus is especially important to help protect and rebuild your bones.

Don’t worry. Every batch of AlgaeCal Plus is thoroughly tested for purity and safety.

Like all plants that grow in soil or water, the marine algae from which AlgaeCal Plus is sourced naturally contains dozens upon dozens of trace minerals, including tiny amounts of lead. But this isn’t unique. Carrots from your garden, broccoli from your local store, and the kale in your salad all contain these same trace amounts. That’s because lead is a naturally occurring element found in soil, water, and air. Plants absorb tiny amounts of it as they draw in minerals to grow. The key point is the amount: these trace levels are extremely small, far below regulatory safety limits, and your body is well equipped to clear them daily through normal processes like urine, stool, and sweat.

To ensure exceptional safety and quality:

- Every lot of AlgaeCal is third-party tested for heavy metals, mineral content, and microbial activity.

- The finished product is manufactured in an FDA-registered, GMP-certified facility that follows the highest quality standards.

- AlgaeCal Plus has 20 years of market use, three human clinical studies, and a full toxicology study demonstrating extraordinary safety.

In fact, a 7-year clinical trial found no-adverse side effects among any of the 172 study participants. 

So you can feel confident knowing that AlgaeCal Plus delivers pure, plant-based nutrients, clinically supported to increase bone density and rigorously tested to meet or exceed all safety guidelines.

Yes. All prescription bone medications require adequate calcium to give your body the raw materials it needs to build new bone. And AlgaeCal Plus provides a clinically supported, plant-based calcium that works beautifully alongside these treatments.

That said, it’s always important to check with your healthcare provider before making any changes to your supplement routine or medical care, especially if you’re currently taking prescription medications.

Yes. But timing matters. To avoid any potential interactions and to ensure the best absorption of both your supplements and medications, it’s best to take AlgaeCal Plus at least 2–3 hours apart from prescription drugs. Some medications may require a 3–4 hour separation, so always check with your doctor or pharmacist for your specific situation.

Special note for blood thinners:

If you are taking an older anticoagulant (such as warfarin or Coumadin), vitamin K2 is not recommended because these drugs use the same absorption pathway and can block each other. Newer anticoagulants—called Factor Xa inhibitors (e.g., apixaban, rivaroxaban) and Direct Thrombin inhibitors (e.g., dabigatran)—do not interfere with vitamin K2 and may be safer for your bones. Ask your doctor if one of these newer options is appropriate for you.

As always, consult your healthcare provider before adding any supplement or making changes to your medication routine.

Many doctors, especially those open to natural treatments, are already familiar with AlgaeCal. But every healthcare provider is different, and it’s always best to give them the full details yourself.

To make it easy, we’ve created a “Take It to Your Doctor” information sheet that outlines the clinical research, ingredients, and dosing. Print it out or share it at your next appointment so your doctor can give you the best, personalized guidance for your bone health.

AlgaeCal Plus contains only a tiny amount of naturally occurring iodine. This is well within the normal range found in many everyday foods. For example three medium-sized potatoes will contain roughly 180 mcg.

However, if you have a thyroid condition, it’s always wise to check with your doctor to confirm that this amount is appropriate for your individual needs.

For best absorption and to avoid any interaction with thyroid medications, take AlgaeCal Plus at least 4 hours apart from your thyroid prescription.

Yes. AlgaeCal Plus contains absolutely no shellfish or shellfish-derived ingredients.

And many customers with shellfish allergies take AlgaeCal Plus safely with no adverse reactions. That said, if you have a severe allergy, it’s always best to consult your doctor or allergist before starting any new supplement.

The U.S. Food and Drug Administration (FDA) does not “approve” dietary supplements. It only approves prescription medications. Because AlgaeCal Plus is a natural supplement, it isn’t eligible for FDA approval.

However, AlgaeCal is registered with the FDA and holds GRAS status (Generally Recognized as Safe). GRAS means a qualified panel of independent experts has reviewed the science and determined the ingredient is safe for its intended use.

No. AlgaeCal Plus is vegetarian. But not vegan. The calcium and other minerals come from plant-based marine algae, but the vitamin D3 is derived from lanolin (the natural wax found in sheep’s wool) which is an animal by-product.

Lanolin is sustainably harvested and does not harm the animals, but because it originates from an animal source, AlgaeCal Plus is classified as vegetarian, not vegan.

Yes. AlgaeCal Plus is completely free of gluten, soy, and dairy—and it’s non-GMO.

AlgaeCal Plus provides magnesium from two sources:

- Naturally occurring magnesium from the organic marine algae Mesophyllum superpositum.

- A small amount of added magnesium oxide to achieve an optimal 2:1 calcium-to-magnesium ratio. This is the same balance found in healthy human bone and the exact ratio used in the clinical studies on AlgaeCal.

Research shows that this precise magnesium ratio, when taken within the AlgaeCal Plus protocol, is clinically supported to increase bone density.