A blood test measures your vitamin D level as 25(OH)D. Uth-FastD™ contains this form, as calcidiol (calcifediol) monohydrate. One small tablet a day.
On sale soon. You can use the code at launch.
Your body first converts D3 into 25(OH)D3 in the liver. Uth-FastD™ starts halfway along this path, with the form in which the conversion step is already complete.
Comes from food, from your skin in sunlight and from D3 supplements.
In the liver, D3 is converted into 25(OH)D3, that is, calcidiol.
A blood test measures your vitamin D level in this form, as 25(OH)D.
Made with VitamoreD™ technology, it contains the form in which the liver conversion step is already complete.
Calcidiol (25(OH)D3) is the form in which the liver conversion step is already complete. In the body it sits one metabolic step further along than D3. D3 and calcidiol are two points on the same path.
Why does a blood test look at 25(OH)D and not D3? D3 stays in the blood for a short time and does not show your vitamin D status on its own. 25(OH)D stays in the blood for a long time. That is why vitamin D status is assessed with this value.
The series takes its name from the word "Youth". We thought of life in three stages: birth, growth and a third stage in which we focus on keeping our vitality. We called that stage Uth. Uth-FastD™ is the first product in the Uth series.
The start of life.
Development, learning and maturity.
The stage focused on keeping your vitality.
The calcidiol in Uth-FastD™ starts its journey with VitamoreD™ technology, developed in the United Kingdom.
The raw material comes from yeast.
The yeast-based raw material is enriched by exposure to sunlight (UV), and the calcidiol is obtained from it.
The tablets are made in the United Kingdom. Every batch is tested by an independent laboratory.
Coming soon to the online store and member pharmacies.
The claims belong to the nutrient (vitamin D), not to the product.
Vitamin D contributes to normal absorption/utilisation of calcium and phosphorus.*
Vitamin D contributes to normal blood calcium levels.*
Vitamin D contributes to the maintenance of normal bones.*
Vitamin D contributes to the maintenance of normal muscle function.*
Vitamin D contributes to the maintenance of normal teeth.*
Vitamin D contributes to the normal function of the immune system.*
Vitamin D has a role in the process of cell division.*
*Health claims apply when the nutrient is consumed in sufficient amounts.
To add up the vitamin D in the supplements you take, you can find the IU to µg conversion in the vitamin D guide.
Once it is on sale, you can order through longevicalsmarket.com (in Turkish) for delivery anywhere in Türkiye. The 20% launch code is valid in this channel.
Take the Vitamin D Test, Get Your 20% CodeTake the Test, Get 20% OffOnce it is on sale, you can ask at your nearest member pharmacy like this: "Kalsidiol formunda D vitamini, Uth-FastD™." (Vitamin D as calcidiol, Uth-FastD™.)
Find Your Nearest Member PharmacyFind a PharmacyRegular D3 (cholecalciferol) is first converted in the liver into 25(OH)D3, that is, calcidiol. Uth-FastD™ contains this form, calcidiol. Calcidiol is the form in which the liver conversion step is already complete, and it is the same 25(OH)D form that a blood test measures.
Uth-FastD™ is a tablet, not a capsule. The tablets, made with VitamoreD™ technology, are very small and easy to swallow. You take one tablet a day. It comes in two sizes: 30 tablets and 60 tablets.
No. Uth-FastD™ is a food supplement, not a medicine, and it must not be used to diagnose, treat or prevent any disease. Food supplements are not a substitute for a normal diet.
Calcidiol (calcifediol, 25(OH)D3) is the form of vitamin D made in the liver. It is the same 25(OH)D form that a blood test measures. In Uth-FastD™ the active ingredient is calcidiol monohydrate. Uth-FastD™ offers this form in a small tablet made with VitamoreD™ technology.
VitamoreD™ is a vitamin D technology developed in the United Kingdom. The calcidiol in Uth-FastD™ comes from a yeast-based raw material that is enriched by exposure to sunlight (UV). The tablets are made in the United Kingdom.
Yes. Every production batch is tested by an independent laboratory in the United Kingdom, and a certificate of analysis (CoA) is issued for that batch. You can request the certificate by writing to bilgi@longevicals.com with the batch number on your box.
One tablet a day. You can take it with or without food. Each tablet contains 10 µg calcidiol, declared on the label as the equivalent of 25 µg vitamin D. Do not exceed the recommended daily intake.
If you take another vitamin D supplement or a multivitamin that contains vitamin D, consult your physician or pharmacist before taking it with Uth-FastD™. Keep track of your blood levels with your physician and do not exceed the recommended daily amount.
Do not exceed the daily amount on the label, which is 1 tablet. When you get vitamin D from more than one source, the total amount adds up. So if you take another vitamin D supplement or a medicine, are pregnant or breastfeeding, or have a health condition, consult your physician before use. If you notice anything unexpected, stop taking it and consult your physician. You can also tell us at bilgi@longevicals.com.
Your physician decides how long you take it and when your vitamin D level (25(OH)D) is measured again. At one tablet a day, the 30-tablet box lasts 30 days and the 60-tablet box lasts 60 days.
Consult your physician before taking Uth-FastD™ during pregnancy or breastfeeding.
Uth-FastD™ is suitable for ages 11 and over. Do not give it to children under 11. Keep the product out of the reach of children.
Uth-FastD™ is coming soon to our online store and member pharmacies. To hear on the day it goes on sale, complete the vitamin D test on this page and leave your email address.
When Uth-FastD™ goes on sale, everyone who completed the vitamin D test and left an email address receives a 20% discount code for their first order by email. The discount applies to the recommended retail price, which will be announced when the product goes on sale, and is valid at the longevicalsmarket.com online store. The code is valid for 30 days from the date it is emailed. The terms of use are in the email.
Uth-FastD™ tablets are made in the United Kingdom.
Uth-FastD™ was developed for people who want to add vitamin D to their daily routine with one small tablet. Food supplements are not a substitute for a normal diet. Pregnant women, breastfeeding mothers, people taking medicines and people with a chronic illness should consult their physician before use.
Uth-FastD™ goes on sale soon. Complete the short vitamin D test and leave your email address. When the product goes on sale, we will let you know and email you a 20% discount code for your first order.
This test is currently available in Turkish only.
Product approval details: Uth-FastD™ · Food Supplement Containing Vitamin D3 · 30 and 60 tablets · approval no. 027096 · 07.08.2026
This is a food supplement, not a medicine. It must not be used to diagnose, treat or prevent any disease. A varied, balanced diet and a healthy lifestyle are important. If you are pregnant or breastfeeding, take medicines or have a chronic illness, consult your physician before use.
Do not exceed the recommended daily intake. Keep out of the reach of children. Consult your physician or pharmacist before using it together with another vitamin D supplement.
*Health claims apply when the nutrient is consumed in sufficient amounts.
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