Costco Vitamins
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Costco Vitamins: Are Kirkland Supplements Safe?

Costco Vitamins Quick Summary

Costco Vitamins have decent dosings for your daily nutritional needs but when it comes to the quality of these vitamins, you may be getting mostly synthetic nutrients. Synthetic nutrients are cheaper to produce, which is why Costco Vitamins are so affordable, but it can also be more difficult for your body to absorb and use these nutrients.

If you want a complete multivitamin that uses whole food sources with the best bioavailability, check out our top multivitamin review here.

Costco Vitamins and Supplements

Costco is a popular household name nowadays, and it’s easy to see why.

This warehouse sells everyday household items in bulk, passing on the value to you. In order to take advantage of the savings at Costco, you have to be a Costco member, by paying a yearly fee and using their membership card.

They take the savings even further by developing their own generic brand name “Kirkland.” Their motto claims “Kirkland Signature means quality and value.” They pride themselves on providing the same products as brand names but cheaper and in bulk.

It’s not surprising that the Kirkland Signature brand has branched out to supplements since 1995. This makes it a lot more accessible for people on a budget to find the supplements they need.

However, when it comes to your health, would you be willing to risk quality for quantity?

In this review, we take a look at some popular Costco Vitamins and see the quality and value behind the Kirkland brand.

Costco Vitamins Review

Kirkland Multivitamin Review | Costco Gummy Vitamins

When looking for a multivitamin, you want to be aware of some things like:

  • What vitamins are included
  • Dosing of those vitamins
  • Any additives or synthetics

Not a lot of people know what to look for in a multivitamin; all we usually know is that we need to get enough (usually 100%) of our recommended vitamins and minerals.

Some vitamins are water-soluble, meaning that having too much of a certain vitamin will just have the excess flushed out of your body. But other vitamins, such as Vitamin A, may cause unwanted side effects if overdosed.

Not only that, but the source of the vitamins are also important to consider.

There are two types of nutrients called natural and synthetic, also known as isolated.

Natural nutrients come from whole foods in your diet or produced from 100% plant-base or animal-base. Synthetic nutrients are usually manufactured artificially. Most of the supplements found on the market are produced with synthetic nutrients.

Though synthetic nutrients may seem structurally similar to natural nutrients, your body may not absorb it as easily due to any hidden additives from the manufacturing process.

If your body can’t absorb it, you may experience potential side effects or your body will only be able to absorb a little of the nutrients.

That’s why it’s important to check the ingredients label and the dosing of all the supplements you plan to take.

Next, we’ll be reviewing some Kirkland Multivitamins and their nutrient profile to see if they’ll be effective for you.

Read our #1 multivitamin review

Daily Multi | Kirkland Multivitamin Review

We’ll be talking about this Costco Vitamin, called the Daily Multi, which claims to have the nutrients to support bone, immunity, eye health and more.

Costco Vitamins and Supplements


  • USP certified
  • Good nutrient diversity


  • Contains gelatin (not vegan-friendly)
  • Contains a high amount of Vitamin A
  • Synthetic nutrient forms

This Kirkland Multivitamin Daily Multi is adequate in terms of its nutrient diversity, however, it concerns us that there is 117% of Vitamin A. Vitamin A is a fat-soluble vitamin, meaning that high levels of it can lead to hypervitaminosis.

We wouldn’t recommend this Costco vitamin as the risk of exceeding the supplementation of Vitamin A is high.

Read our #1 multivitamin review

Costco Vitamins for Seniors | Kirkland Mature Multi-Vitamins

Kirkland Mature Multi is a multivitamin that claims to be able to support the overall health of individuals over 50 by providing essential micronutrients.

Costco Vitamins For Seniors


  • Contains a high amount of Vitamin B12
  • Contains less Vitamin A
  • USP Certified


  • Contains gluten (not vegan-friendly)
  • Nearly identical to Daily Multi
  • Synthetic nutrient forms

We like that there is much more Vitamin B12, however, the other nutrient changes aren’t significant enough to really make a difference.

Also, let’s not forget that these are synthetic nutrient forms so it’s not certain how well these Costco vitamins and minerals will be absorbed.

Other than the slightly higher nutrient doses for certain vitamins and minerals, Kirkland Mature Multi is nearly identical to Daily Multi with extra Vitamin B12, so this may not be the best multivitamin for seniors.

Read our #1 multivitamin review

Kirkland Adult Multivitamin Gummies | Costco Multivitamin Gummy

Costco vitamins also include Kirkland Adult Multivitamin Gummies which claim to be a delicious and easy way to get your essential nutrients to support bone and immune system health.

Costco Multivitamin Gummy


  • Contains 10 essential vitamins
  • Low sugar


  • Low nutrient diversity
  • More vitamins than minerals
  • Contains gelatin (not vegan-friendly)
  • USP certified

These Costco Multivitamin gummies are not USP certified, meaning they haven’t been approved by the United States Pharmacopeia which has strict standards on supplement manufacturing.

These Kirkland Multivitamin gummies aren’t the best for nutrient supplementation. There are more vitamins than minerals in the multivitamin formula, possibly because it would affect the taste of the gummies.

Read our #1 multivitamin review

Costco Prenatal Vitamins | Women’s Multivitamin

When selecting the best prenatal vitamin, these nutrients are the most important for a woman during pregnancy:

Folic Acid – Also known as Vitamin B9, this helps prevent serious neural tube defects by helping the body with cell synthesis.

Iron – This mineral is used for red blood cell production and is especially important in preventing anemia in women which causes them to feel fatigued and irritable.

Calcium – Calcium is necessary for bone growth and health during pregnancy.

Vitamin D – Vitamin D aids the body in absorbing Calcium as well as supporting the baby’s immune system, bones, nerves, and muscle.

Omega-3 – These fatty acids help support the baby’s brain, heart, and eye development during pregnancy.

Iodine – This nutrient is crucial for pregnant women to help regulate their hormones, thyroid, and nervous system.

Costco Prenatal Vitamins

It would be beneficial for pregnant women to get all of these important nutrients in a simple and effective prenatal vitamin.

We’ll be taking a look at what Costco Vitamins currently offer for prenatal vitamins at the time of this review (October 2019).

Read our #1 multivitamin review

Smarty Pants Vitamins Costco

Costco currently sells the popular vitamin brand Smarty Pants Prenatal Complete which claims to have premium nutrients for expecting mothers and their babies.

Smarty Pants Vitamins Costco


  • Easy to take
  • No synthetic colors or artificial flavors
  • Contains most of the important prenatal nutrients
  • USP verified ingredients


  • Contains 7 grams of sugar per serving
  • 6 gummies per serving
  • No iron
  • Low amount of DHA

SmartyPants states that iron is the leading cause of supplemental overdose in children under 6, so they decided to leave it out of their formula. This is understandable if children were to think this was candy, however, this would require women to get iron from source to prevent anemia.

DHA in Omega-3 is important for fetal brain development and requires at least 200 mg daily. SmartyPant Prenatal only provides 48 mg.

Since this is a gummy vitamin, it’s a given that there is added sugar to make it taste better, however, we think 7 grams of sugar is a bit high for a daily serving.

But if the lack of iron and DHA isn’t an issue, then Costco SmartyPants Prenatal Complete is an okay choice.

Nature Made Prenatal Costco Multivitamin

Another Costco Vitamin is Nature Made Prenatal Multi + DHA which claims it is specially formulated to support prenatal development and has clinically proven absorption.

Nature Made Prenatal Costco


  • Contains 18 nutrients
  • Decent dosages
  • 1 soft gel
  • USP verified


  • Not enough Iodine
  • Low Calcium

Iodine is important for hormone regulation in both the pregnant mother and the baby but the dosage is a bit low in Nature Made Prenatal Multi. The dosage of Calcium for bone development is also low.

But overall, Nature Made Prenatal at Costco is a good choice for the most complete nutrients for expecting mothers.

Read our #1 multivitamin review

One a Day Prenatal Costco

This Costco Prenatal Vitamin from One a Day claims to be a complete multivitamin that works for each stage of pregnancy. However, it’s only available online at the Costco website, not in-stores.

Costco Prenatal One a Day


  • 800 mcg of Folic Acid
  • 200 mg of Omega-3 DHA
  • Good nutrient diversity
  • 1 Tablet


  • Contain Gelatin (not vegan-friendly)
  • Not USP Certified
  • Low Calcium

Despite claiming to be a complete multivitamin, there is a low amount of Calcium included. Pregnant women need at least 1,000-1,300 mg of Calcium for healthy bone development, while One a Day Prenatal only provides 300 mg.

Calcium is a heavy nutrient to include in a multivitamin so it’s understandable that they can’t provide 100% Daily Value of Calcium.

Overall, this is a good Costco One A Day Prenatal multivitamin for expecting mothers because of the extra support from Folic Acid and Omega-3 DHA.

Kirkland Multivitamin Review

Costco Vitamins Review

Costco provides a good variety of Kirkland Vitamins and name-brand supplements at a good value.

However, most of these Costco Vitamins contain synthetic forms of these nutrients which explain why Kirkland Signature supplements are so affordable.

With synthetic nutrients, it’s uncertain if the vitamins and minerals will be absorbed as well in your body compared to whole foods or whole-food vitamins.

While there are safe dosings and adequate Daily Values in the multivitamins, there’s no telling how your body will react to synthetic nutrients and no guarantee if you’ll be getting the most health benefits out of these Costco Vitamins.

Would we recommend Costco Vitamins? Possibly.

Costco Vitamins are a good value for the absolute basic vitamins and supplements. However, if you’re looking to get the best health benefits and start feeling and living better, we’d recommend a whole-food multivitamin so your body can absorb the most nutrients from whole food sources.

Our #1 Recommended:
Performance Lab Multi

Performance Lab Whole Food Multi
Out of all the multivitamins we've reviewed so far, Performance Lab Multi is definitely the best option we've come across at the moment.With all natural ingredients, generous dosages and a focus on nature-identical nutrients, it's by far one of the most impressive options on the market at the moment to give yourself the vitamins and minerals that nature intended.

It works well for helping:

  • Promote General Health
  • Restoring Deficiencies In Your Diet
  • Optimizing Hormones
  • Deliver Gender-Specific Nutrients to fully nourish your body

To see numerous reviews, along with our personal take on this multivitamin click the link below to read our full take on it.

Click below to read our
Performance Lab Multi Review