Medically Reviewed

How Long Does It Really Take for Supplements to Work? Experts Explain the Timeline

Vitamins and supplements can support your health in important ways. How long they take to work depends on a variety of factors. Read on to learn more.

What happens to your body when you start taking vitamins?

Your body needs vitamins to function at an optimal, proper level. Specifically, your body needs 13 vitamins. Nine of these vitamins are water-soluble, and four are fat-soluble.

While these nutrients are largely available through dietary means, it’s still possible to have vitamin deficiencies. Vitamin supplements can help fill in nutrient gaps and get your body functioning the way it should – helping you feel your best! If you start taking vitamins in response to a vitamin deficiency in your body, you’ll likely be feeling the benefits before long. However, the rate at which you’ll notice the impact may vary, based on a number of factors.

Do vitamins start working immediately?

Many people will start to feel better soon after starting their vitamin regimen. Once you take a vitamin, it starts to have an impact on the biochemical processes in your body. You might notice an increase in your energy levels, improved cognitive function, decreased fatigue, and an overall sense of wellbeing.

That said, whether or not you feel an immediate impact depends on a number of factors, the most important of which is whether you’re deficient in the vitamin you’re taking. If you are, you’ll be more likely to notice an impact in a shorter time. And that’s not because of a placebo effect: If a doctor were to examine your blood levels after taking a new vitamin, you’d see the change. Some vitamins, though – such as vitamin D – take a little longer to be reflected in numerical changes in a lab.

Moreover, the speed at which you’ll start to notice the impact of your vitamin regime can depend on a few key factors. Let’s take a look at them.

The timeline depends on a few key factors

Vitamin quality

When it comes to how well and how quickly you can expect your vitamins to work, the vitamin quality is important. Some companies, including Care/of, test for purity to ensure that what’s advertised on the label is indeed what’s in the supplement. Care/of also employs third-party testers. When you’re looking at a supplement bottle, check for quality seals and third-party certifications.

Consistency of regimen

To maximize the benefits of vitamin supplementation, consistency is the key. When you’re starting on a new vitamin routine, it’s a good time to check in with yourself and see how you’ve been feeling. The Care/of app can be a helpful tool in this effort, offering you personalized guidance, tracking your progress, and helping you stay on top of your routine. You can also use it to handle new orders and to earn rewards.

Whether you have a deficiency

If you’re experiencing a deficiency in certain vitamins or minerals, you may be somewhat likely to notice a pretty immediate difference.

For example, those experiencing a vitamin B12 deficiency often feel this as excessive fatigue. For such people, taking a vitamin B12 supplement can lead to a noticeable difference, particularly compared to those who do not have a deficiency.

The vitamin form: water vs. fat soluble

As mentioned above, vitamins come in two forms: water-soluble and fat-soluble. And the form can have an effect on how quickly they work in the body.

The biggest difference between water-soluble vitamins and fat-soluble vitamins is how they’re absorbed and stored by the body. Water-soluble vitamins dissolve in water and aren’t stored in the body; once the body gets what it needs, the excess is flushed out. Fat-soluble vitamins, on the other hand, are absorbed by fat that then goes through your bloodstream, ultimately getting stored in the liver.

These differences can account for the differences in their effect in your body. Since water-soluble vitamins are absorbed more quickly, you might notice their impact sooner. Moreover, since fat-soluble vitamins get stored by the liver, taking too much of a fat-soluble vitamin can have toxic effects. It’s important to check with a medical professional about your vitamin levels before making changes to your vitamin regimen.

How the vitamins are stored

Proper storage of your vitamins is essential to a healthy vitamin routine. You should keep your vitamins stored in a cool dark area, away from sunlight and humidity. This will help ensure that they remain high quality.


While lifestyle adjustments won’t speed up the process of a vitamin working in your body, they can make sure your vitamin regimen has the maximum possible impact. Some steps you might consider include: getting more sleep, eating a nutrient-rich diet, exercising, and staying hydrated. You can also consider cutting back on less healthy habits, like consuming too much alcohol or smoking.

How do you know whether vitamins are working?

It can take time to know whether your vitamins are working. As noted above, if you are deficient in a particular vitamin, taking that vitamin in supplement form can lead to some pretty immediate benefits. In other cases, it may take some time. Let’s consider some examples.

Care/of’s veggie collagen should promote joint comfort within a 7-10 day span, and research shows that the eggshell membranes used to make this supplement is fast-acting for joint comfort. Magnesium, when used for the relief of muscle-related soreness, has been shown to be effective after just 10 days of supplementation. Care/of’s magnesium is sourced from Irish seawater and contains more than 70 trace minerals. Care/of’s digestive enzymes work quickly, particularly since they’re taken with food. You may notice some relief in gas and indigestion within a few days, or possibly even right away. Our vitamin D3 is great quality, but it can still take at least 3 months to see a chance in vitamin D lab numbers. As always, consistency is the key. And, as one final example, our Focus Blend, designed to support cognitive focus, is meant to be felt right away. It’s recommended that you take 60 minutes before you need to focus.

Here’s the point: Your ability to tell whether your vitamins are working depends on which vitamins you’re taking and for what purpose. It’s always a good idea to consult with a medical professional to learn more about how certain vitamins will work in your body.

Can you speed up the process?

The effects of vitamin supplements largely depend on the factors outlined above: vitamin quality, consistency of your vitamin routine, how the vitamins are stored, and overall lifestyle.

While you can’t speed up the process of how a vitamin will work in your body, you can maximize a vitamin’s impact through some lifestyle tweaks. These can include:

  • Getting adequate sleep
  • Eating a healthy, nutrient-rich diet
  • Exercising
  • Staying hydrated

All of these steps will help put your body in the best possible position to benefit from a vitamin regimen.

Key takeaways

Your body needs 13 vitamins to be able to function properly – 9 that are water-soluble, and 4 that are fat-soluble. Vitamin supplements can be a good idea for people who are experiencing nutrient deficiencies. How long it takes your vitamin supplements to work depends on a variety and factors and can vary from person to person. Some are designed to work swiftly, while others will necessarily take more time. The key to a successful vitamin regimen is to make sure you’re getting the best quality vitamins, like those offered here at Care/of, and that you’re consistent in your routine. If you need some encouragement staying on track with your routine, the Care/of app can help – consider checking it out!

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