Clinical Studies

Efficiency of Different Cholecalciferol Formulations in Treating Suboptimal Vitamin D Status

Vitamin D plays a very important role in the human body as it contributes to the maintenance of normal bones and normal function of the immune system. Numerous reports showed high prevalence of low vitamin D intake and vitamin D deficiency in Europe – particularly during the winter season, indicating the importance of vitamin D supplementation. There is however some confusion regarding the dosages, as different associations recommend different amounts of daily intake of vitamin D. Question about appropriate dosing and formulation of vitamin D supplementation therefore arises. To get a more accurate answer to that question, Valens initiated a study about treating suboptimal vitamin D status that was conducted in Slovenia.

Goal: To investigate the efficiency of treating suboptimal vitamin D status with 25 µg (1000 IU) of vitamin D3 per day using different vitamin D3 (cholecalciferol) formulations, which are most commonly used in supplements.

Method: Two-months randomized controlled intervention study was conducted on 105 humans with suboptimal vitamin D status (12-20 µg/L). Subjects were aged from 18 to 65 years and had no previous treatment with vitamin D. The trial was conducted in Slovenia by Nutrition Institute during winter time; supplementation started in January and ended in March 2019. 21 % of initial 235 human subjects had severe vitamin D deficiency (<12 µg/L) and only 105 were able to participate in the study. 99 (94 %) subjects finished the trial successfully. During the study, the treatment group was taking 25 µg (1000 IU) of vitamin D while control group was receiving no supplementation at all.

Valens Vitamin D supplements, used in the trial

1. Valens D-Natural – oral spray (1000 IU/25 µg of D3), oil-based

2. Valens D 1000 – oral spray (1000 IU/25 µg of D3), water-based

Results of the study

1. Both tested Valens Vitamin D formulations are efficient in improving suboptimal vitamin D status. 99 (94 %) participants finished the trial successfully. Daily supplementation of 1000 IU vitamin D during winter resulted in considerable increase in average serum vitamin D levels (for 13 mg/L) in both treatment groups using Valens vitamin D oral sprays. Average serum vitamin D levels were also considerably higher compared to the control group. On the other hand, control serum vitamin D level in the control group was further lowered from January to March.

2. Inhabitants of Continental Europe don’t get enough vitamin D in the winter time due to inadequate exposure to sunlight. The study confirmed high prevalence of vitamin D deficiency in the winter season. 66 % of the subjects had suboptimal serum vitamin D levels ( 20 µg/L), while 21 % had serum vitamin D levels even below 12 µg/L. Those weren’t able to participate in a study.

3. Most participants required higher dosages for reaching optimal vitamin D status. The study indicates that the dosage of 1000 IU daily might not be sufficient for maintaining optimal vitamin D status during winter. After 2 months of supplementation, serum vitamin D levels were still below 30 mcg/L in 77% of the subjects, indicating they would either need higher doses of vitamin D or should start with supplementation earlier.

 Chart: Supplementation with Vitamin D (1000 IU daily) during winter resulted in considerable increase in average serum vitamin D levels. The increase was statistically significant compared to both – control group and initial serum vitamin D level.

Serum vitamin D level in the control group was further lowered (from 15.8±2.5 µg/L to 14.3±2.6 µg/L) from January to March, which confirmed winter time (absence of sun) as an appropriate period for this study.

Daily supplementation of 1000 IU of Valens water-based vitamin D oral spray resulted in considerable increase in average serum vitamin D levels (from 15.6 ± 2.1 µg/L to 26.4 ± 5.2 µg/L (N=26).

Daily supplementation of 1000 IU of Valens oil-based vitamin D oral spray resulted in considerable increase in average serum vitamin D levels (from 15.8 ± 2.2 µg/L to 27.6 ± 7.7 µg (N=26)

Results publication: The preliminary results of the study were presented at the International conference Nutrients 2019 – Nutritional Advances in the Prevention and Management of Chronic Disease (25.-27. September 2019), the scientific article is being prepared to be published.

Improved bioavailality of water-soluble CoQ10 – Q10Vital® 

Coenzyme Q10 (CoQ10) plays a very important role in the human body. Present in every cell in the body, it is concentrated in organs that require the most energy – such as the heart, liver, muscles and kidneys. Efficiency of the biosynthesis of CoQ10 progressively decreases with age and supplementation with CoQ10 is thus relevant with older people. Several studies of CoQ10 supplementation showed beneficial effects, particularly in relation to cardiovascular health and aging. The key to effective supplementation is its bioavailability, however most studies of CoQ10 bioavailability were so far conducted on younger population. As beneficial effects of CoQ10 supplementation is more relevant with older population, Valens initiated a new comparative study of three CoQ10 formulations in healthy older adults. The aim was to prove superiority of water-soluble ubiquinone Q10Vital® compared to standard CoQ10 and ubiquinol formulations.

GoalsFirst goal was to investigate and prove better bioavailability of Q10Vital® compared to capsules containing standard ubiquinone and soft-gel capsules containing ubiquinol. Second goal was to investigate and prove that there are no differences in the redox status of the absorbed CoQ10 in older adults.

Method: Randomized, three-period crossover bioavailability study was conducted on 21 healthy older adults aged from 65 to 74. Only healthy subjects were included with no prior supplementation. Treatment was done as a single dose with one-week wash-out period, using three different formulations containing equivalent of 100 mg CoQ10: capsules containing basic ubiquinone, soft-gel capsules containing ubiquinol and syrup containing water-soluble ubiquinone Q10Vital®. Plasma ubiquinone/ubiquinol level was followed for 48 hours.

Valens products, used in the trial

Q10Vital®, water soluble CoQ10 in the form of a syrup (commercial name of the syrup: Quvital®*

*It is also available in the form of an oral spray and capsules.

Results of the study

1.Bioavailability of Q10Vital® was 2.4-fold higher compared to standard CoQ10 and 1.5-fold higher compared to ubiquinol. When orally administrated, standard CoQ10 has limited bioavailability. Due to water solubility, bioavailability of Q10Vital® is improved, which has been proven several times before (up to 4-times better bioavailability compared to standard CoQ10). Two formulations with expected improved bioavailability were compared to a standard formulation in this study, and Q10Vital® had been proven to be superior in the terms of bioavailability even in older adults, which are believed to have limited absorption of nutrients in the digestive system.

2. Regardless of ingested formulation, reduced form (ubiquinol) appears in the blood. No significant differences in the redox status of the absorbed CoQ10 had been noted. 90% of all absorbed CoQ10 in the blood was in reduced form. CoQ10 appears in blood almost exclusively as ubiquinol, even when ingested ad ubiquinone. Ubiquinone to ubiquinol conversion is unobstructed even in older adults, although it was previously believed that conversion is limited in those.

3. Ubiquinol formulations are in no way superior to ubiquinone formulations. CoQ10’s function in the body is not affected by the form it is ingested in. The key challenge is the initial CoQ10 absorption, which has been proven to be highly improved in Q10Vital®, compared to both, standard and ubiquinol formulation.

Chart: Supplementation with all three formulations resulted in higher plasma CoQ10 level. Bioavailability of Q10Vital® was 2.4-fold higher compared to standard CoQ10 and 1.5-fold higher compared to ubiquinol.


Better relative bioavailability of CoQ10 in form of Valens Q10Vital® over standard product was determined in older adults. No differences in the redox status of the absorbed coenzyme Q10 were observed between formulations, showing that the CoQ10 appears in blood mostly as ubiquinol, also if consumed as ubiquinone.

Results publication: The article “Comparative Bioavailability of Different Coenzyme Q10 Formulations in Healthy Elderly Individuals” has been published in Nutrients as part of the Special Issue Nutritional Advances in the Prevention and Management of Chronic Disease in March 2020.

Effects of a combination of Water-Soluble Coenzyme Q10 and Collagen on skin Parameters and Condition

Due to increased life expectancy, more and more focus is placed on overcoming challenges related to aging. As changes in skin appearance are often the first visible signs of aging, a lot of research is dedicated to reduction of those signs. Skin is a complex organ that provides protective interface between the external environment and the body. Genetics, environmental factors such as sun exposure, ultraviolet radiation, smoking, sleep deprivation, pollution, and nutritional factors are what affects skin-aging process the most due to changes in dermal collagen network and formation of free radicals. Wide range of nutritional supplements, including collagen and CoQ10 have already been examined and proven to have beneficial effects on skin, however the effect of a combination of CoQ10 and collagen has not yet been investigated. Hence, Valens initiated a new study to prove beneficial effects of supplementation with CoQ10 and collagen complex on skin.

Goal: To investigate the effects of liquid food supplement containing a combination of water-soluble coenzyme Q10 (Q10Vital®) and collagen peptides on dermal density, wrinkle area, skin-smoothness and other skin parameters.

Method: Randomized, double-blind placebo-controlled study was conducted on 34 healthy women. Subjects were aged 40-65 and had no prior similar supplementation. They consumed 10 ml of a syrup daily for 12 weeks. The test group received a syrup with 4000 mg of hydrolyzed fish collagen, 50 mg of water soluble CoQ10 with improved bioavailability (Q10Vital®), 80 mg of vitamin C, 920 µg of vitamin A and 150 µg of biotin per 10 ml. The placebo group consumed flavored and colored syrup without active ingredients. Measurements and assessments of skin were made at baseline and after 12 weeks of intervention. 31 subjects completed the trial.

Valens food supplement, used in the trial

Valens Premium Collagen Complex – Liquid supplement with Q10Vital®, hydrolyzed fish collagen, vitamin C, vitamin A and biotin

Results of the study

1.Significantly higher dermis density. After 12 weeks of supplementation with Valens Premium Collagen Complex, the dermis density in test group was significantly higher in comparison to placebo group, as well as to baseline in the test group. Dermal density is mostly related to the amount of collagen (and elastin), yet these results are almost double when compared to one of the previous studies with a higher dose of collagen (10 mg/day) and no CoQ10, indicating synergistic effects between CoQ10 and collagen

2. Decrease in the periorbital wrinkle area fraction. After 12 weeks of supplementation, the evaluated wrinkle area (around the eyes) fraction was significantly lower in the test group. There was no difference between the test and placebo group at baseline.

3. Significantly lower total wrinkle score. With expert assessment of wrinkles of different types in different face areas the total wrinkle score was calculated. In the test group, total wrinkle score was significantly lower after 12 weeks of supplementation, while no difference was observed in the placebo group compared to baseline.

4. Significant improvement in smoothness. Skin smoothness in the test group has improved significantly, while the placebo group even had a slight decline. The improvement in the expression of microrelief lines was also notably higher in the test group compared to baseline, yet not statistically significant compared to placebo group.

Dermal density difference between the placebo and test group was not significant at baseline (before the intake – T0). Oral administration of the test product for 12 weeks (T12) led to increased dermis density, while in the placebo group there was no change in the same period of time.

Periorbital wrinkle area : No difference between test and placebo group was noted at the baseline (T0), yet the oral administration of the test product after 12 weeks (T12) resulted in decreased periorbital wrinkle area in the test group.

Relative change of total wrinkle score after 12 weeks of supplementation for test and placebo group, compared to baseline.

Results publication: The scientific article was published in open access journal Nutrients 2020 on the 27th of February.