Youthful Brain Review: Is It Right For You?

Youthful Brain Review Testing

6th November 2023

Youthful Brain From Vitality Now

In this Youthful Brain review, we thoroughly test and assess this nootropic supplement. In a market flooded with pills claiming to boost brainpower, Youthful Brain by Vitality Now is marketed heavily, but does it stand up to scrutiny? We're about to find out. They've packed it with 1000 micrograms of Vitamin B12 and a proprietary mix that includes plant extracts and brain-friendly compounds—all aimed at keeping your thinking sharp.

But let's be real: fancy names on a bottle don't guarantee results. In this review, we're going to put Youthful Brain under the microscope. We'll look beyond the buzzwords, asking hard questions about whether these ingredients—and the doses they're in—actually match up with the science. And with some eyebrows raised about its claims, we'll also weigh it against other brain boosters on the market. Because when it comes to what you put in your body, you deserve the full picture.

Overall Results And Recommendation


Youthful Brain

51%
Fill Counter

Overall Rating

Youthful Brain Reviews
  • Modest Improvements: Youthful Brain's effects were minimal, offering a slight boost but falling short of the significant cognitive enhancement it promises.
  • Opaque Blends: The proprietary blend masks the exact ingredient amounts, leaving us guessing whether they're at effective levels.
  • Underwhelming Experience: Compared to the best nootropics we've tested, Youthful Brain delivered a less noticeable impact on mental clarity and focus.
  • Clinical Ingredient Absence: Youthful Brain lacks several key ingredients shown in studies to support brain health, limiting its potential efficacy.
  • Unverified Claims: Without transparent research or peer-reviewed studies, the supplement's effectiveness is based on trust rather than scientific proof.
  • Better Alternatives: Our top recommendation is NooCube, which offers a comprehensive, transparently dosed formula that aligns with clinical evidence and has proven to be more effective in our direct experience.

NooCube

92%
Fill Counter

Overall Rating

Youthful Brain Alternative

Quick Decision Guide - Youthful Brain vs Leading Nootropic (NooCube)

CRITERIA

Youthful Brain

Youthful Brain Reviews

NooCube

Youthful Brain Alternative

Overall Rating (From Our Experience Using Each Product)

28%
Fill Counter
92%
Fill Counter

Main Benefits

Claimed improvements to cognitive function, focus and energy

Comprehensive cognitive improvement spanning brain health, cognitive performance and memory with a multi-ingredient blend

Scientific Backing

Lacking transparent research

Strong, with many well-researched ingredients

Formula Complexity

Basic

Comprehensive

Brand Reputation Concerns

Medium, no major issues but lacking in transparency and likely over claims

Minimal to none

Cost

Premium

Premium

Commitment Time for Results

Weeks to months with variable results

Weeks, consistent use recommended

Servings Per Container

30

30

Capsules Per Container

60

90

User Feedback

Mixed reviews

Predominantly positive

Ingredients' Transparency

Opaque proprietary blend

Fully disclosed

Dosage Convenience

2 capsules daily

3 capsules daily

Potential Side Effects

Moderate risk

Low risk

Customer Support & Return Policy

Mixed customer service reviews, 180 day return policy

Excellent, 60 day money-back guarantee

Product Availability

Widely available

Available through official site only

Additional Benefits

None

Boosts neurotransmitters, enhanced neuroprotection

What Is Youthful Brain?

Youthful Brain is a nootropic supplement that has positioned itself as a supportive ally for those over the age of 45, looking to maintain healthy brain function and memory sharpness. Vitality Now, the company behind Youthful Brain, suggests that their product can enhance cognitive function, mental clarity, and focus, while also providing healthy all-day energy in small, easy-to-swallow tablets. However, when it comes to backing these claims with solid scientific evidence, things start to get a bit murky.

The research Vitality Now references regarding the effectiveness of Youthful Brain isn't immediately accessible or transparent. More critically, it appears that the studies haven't undergone the rigorous process of peer review. This raises a red flag, as peer-reviewed research is the gold standard for verifying the validity and reliability of scientific claims. Without this, consumers are left with no choice but to take the brand's word on the supposed benefits of Youthful Brain, which is not an ideal situation when assessing the potential impact on one's health.

The product's exact formulation is another area where clarity is lacking. Vitality Now opts to use a 'proprietary blend'—a controversial practice in the supplement industry, which often leaves consumers guessing exactly what they're taking and in what amounts. This proprietary blend, totaling 370 milligrams, includes Bacopa Herb Extract, Ginkgo Leaf Extract, Phosphatidylserine, and Huperzine A, alongside a significant amount of Vitamin B12. While each of these ingredients has some history of use in traditional or herbal medicine for cognitive support, the proprietary nature means we're in the dark about how much of each ingredient is actually in Youthful Brain. This lack of transparency can be problematic because it makes it difficult for consumers to gauge the supplement's potential effectiveness and safety.

The use of proprietary blends prevents consumers from making informed decisions based on their individual health needs or from comparing the product with other similar options on the market. It also hinders the ability of healthcare professionals to provide accurate advice or to anticipate possible interactions with other medications.

Despite these concerns, Youthful Brain boldly makes its claims. It promises to promote cognitive health, presumably through ingredients like Bacopa and Ginkgo, both of which have historical roots in supporting memory. Phosphatidylserine is included, likely for its role in cell membrane function in the brain, and Huperzine A for its potential effects on neurotransmitter levels. However, without the transparency of ingredient amounts or robust scientific backing, these claims stand on shaky ground.

The small and easy-to-swallow tablet claim is the least contentious, as it is a straightforward physical description of the product. Yet, even this simple characteristic does little to assuage concerns over the lack of scientific rigor and transparency that clouds the more important aspects of efficacy and safety.

To sum up, Youthful Brain by Vitality Now presents itself as a cognitive enhancer for the mature individual, yet it does so without offering the robust scientific evidence or product transparency that consumers deserve when making health-related decisions. As it stands, while the ingredients themselves are not without merit, the shadows cast by the elusive research and the opaque nature of a proprietary blend make it challenging to validate or refute the brand's claims confidently. Therefore, consumers might be wise to approach Youthful Brain with a degree of skepticism.

Youthful Brain's Claims

In assessing the cognitive-enhancing claims of Youthful Brain, it's necessary to look into the research behind its ingredients. The supplement's ingredient list is anchored by Vitamin B12 and a proprietary blend consisting of Bacopa monnieri, Ginkgo biloba, Phosphatidylserine, and Huperzine A.

Vitamin B12, at 1000 micrograms, is well above the daily amount required by the body, which can be beneficial for cognitive health, especially in older adults or those with B12 deficiencies [1]. B12 plays a pivotal role in maintaining the health of neurons and could potentially support cognitive functions when consumed at such high levels [2].

Turning our focus to the proprietary blend, which totals 370 mg, we encounter some challenges. The research-supported dosages for these nootropic agents are substantial, typically exceeding the entirety of Youthful Brain's blend. Effective daily doses of Bacopa monnieri are in the range of 300 to 450 mg [3], while Ginkgo biloba exhibits potential cognitive benefits at 120 to 240 mg daily [4]. Phosphatidylserine is studied with dosages around 100 to 400 mg [5], and Huperzine A's acetylcholinesterase inhibition effect is noted at doses of 50 to 200 micrograms per day [6].

The proprietary blend's stated weight is less than the sum of the lower-end effective doses for these individual ingredients, raising questions about whether the product contains adequate levels of each ingredient. This under-dosing concern implies that each ingredient may not be present in sufficient quantities to replicate the effects observed in clinical studies. Since the exact amounts of each component in the blend are not disclosed, it's challenging to ascertain if they are included at therapeutically relevant levels.

This lack of transparency hinders the ability to verify the efficacy of Youthful Brain based on its ingredient profile. As a result, the supplement's proclaimed benefits such as enhanced mental clarity, focus, and sustained energy levels remain speculative and unsupported by the evidence provided through the lens of its proprietary blend.

For consumers considering Youthful Brain, this analysis underscores the importance of transparency in supplement labeling. While the individual ingredients have been associated with cognitive benefits, the undisclosed quantities within the proprietary blend necessitate a cautious approach to the product's claims.

Manufacturer's Claim: "Youthful Brain is a doctor-approved, premium formula that helps eliminate brain fog".

  • The Reality: While the product is marketed as doctor-approved, without transparency regarding which doctors or specialists have endorsed it beyond those paid to promote the brand, this claim remains unsubstantiated. The potential of the ingredients to mitigate brain fog can be supported by their individual effects; however, given the proprietary blend's under-dosing, its ability to clear brain fog effectively is uncertain.

Manufacturer's Claim: "Enhances memory and boosts overall mental performance".

  • The Reality: Bacopa monnieri has been associated with improved memory in several studies when used at appropriate doses [7]. However, without clarity on the doses within Youthful Brain, it’s not possible to affirm the product’s efficacy in enhancing memory.

Manufacturer's Claim"Targets the areas of the brain where help is needed most".

  • The Reality: The ingredients have been shown to influence cognitive health, but the ‘targeting’ of specific brain areas is a more complex claim that is not directly supported by the broad mechanisms of the ingredients in Youthful Brain. Additionally, the assertion lacks specificity and cannot be quantified without detailed clinical data on the product itself.

Manufacturer's Claim"Carefully sourced and selected for their potency and ability to maximize brain function, regardless of age".

  • The Reality: The ingredients selected are indeed recognized for their nootropic properties; however, 'potency' is directly related to dosage. Since the proprietary blend may not provide adequate amounts of each ingredient, the potential to 'maximize' brain function cannot be taken at face value.

Manufacturer's Claim"Promotes healthy cognitive function".

  • The Reality: The ingredients have individual studies backing their use for cognitive support. For example, Ginkgo biloba extract has been shown to have a small effect on improving cognitive function [8]. Nonetheless, the impact within Youthful Brain is unclear due to the proprietary blend's dosage concerns.

Manufacturer's Claim"Enhances mental clarity and focus".

  • The Reality: Huperzine A, known for its neuroprotective qualities, could play a role in enhancing mental clarity due to its acetylcholinesterase inhibition [9]. However, the lack of precise dosing information for Huperzine A within the blend makes this claim difficult to evaluate.

Manufacturer's Claim"Promotes healthy all-day energy".

  • The Reality: Vitamin B12 is involved in energy production in the body, and its high dosage in Youthful Brain may contribute to increased energy levels [10]. Yet, the all-day energy promotion claim is broad and may not account for individual differences in metabolism and absorption.

Does Youthful Brain Work?

Our Experience With Youthful Brain

Our test drive of 'Youthful Brain' started with a lot of hope. This brain supplement, which hails from the shelves of Vitality Now, promises a lot – sharper thinking, better memory, more energy, and all this for folks mainly over the age of 45. They've even got doctors giving it the thumbs up, so we were keen to see if it really could be the brainpower booster it claimed to be.

The claims are pretty straightforward. Youthful Brain is supposed to:

  • Clear up brain fog.
  • Help you remember better.
  • Keep you sharp and focused.
  • Give you energy that lasts all day.
  • Be easy to take.

So, we took the small tablets, which were indeed no trouble to swallow, and waited for the magic to happen. But after several weeks, we had to admit, the results were pretty underwhelming.

First off, that pesky brain fog. It was supposed to vanish, right? Well, it didn't. We didn't feel that mental cloudiness lift like we've felt with some other top-tier brain supplements we've tried before. The bacopa and ginkgo, both stars in the world of memory and focus aids, just didn't seem to do their job as promised, or at least not to the level we were hoping for.

And what about the mental clarity and focus? We really wanted that to be true. Ginkgo, in particular, has a reputation for sharpening the brain, but we just didn't get that sharpness. Everything felt pretty normal, not the step up we were expecting.

The 'all-day energy' was another claim. With vitamin B12 on the ingredient list, we figured we'd at least feel a bit more pep in our step. But again, no big change. It was business as usual, no extra energy boost that we could see.

Now, let's talk about those ingredients. They've got some heavy hitters in there: bacopa, ginkgo, phosphatidylserine, and huperzine A. All these are known for their brain-boosting properties. But here's the rub – they're tucked away in a proprietary blend. That means we can't tell if there's enough of each to really make a difference. And from what we felt, it seems like maybe there isn't.

We have to be straight with you: compared to other brain supplements we've tested, Youthful Brain didn't quite measure up. The real-life experience just didn't stack up to the brand's big promises. It's not that we felt worse or anything – we just didn't feel the boost we were looking for. It might work for some, but for us, it was a bit of a letdown.

Youthful Brain Pros and Cons


Pros:

  1. Contains Vitamin B12: A vital nutrient for maintaining healthy nerve cells and aiding in the production of DNA and RNA.
  2. Targeted for Older Adults: Specifically aimed at improving cognitive function in individuals over 45.

Cons:

  1. Proprietary Blend: The specific amounts of individual ingredients are not disclosed, making it difficult to evaluate efficacy.
  2. Limited Evidence: There may be insufficient peer-reviewed research supporting the product's specific formulation and claims.
  3. Potential for Inadequate Dosage: The total amount of the proprietary blend may be less than the effective doses for each ingredient.
  4. Slow or Subtle Effects: Limited perceivable benefit, even after several weeks.
  5. Overhyped Claims: Marketing claims might raise expectations beyond what the supplement can actually deliver.

Youthful Brain Ingredients: A Scientific Overview

Youthful Brain Ingredients:

Vitamin B12 (1000mcg), Proprietary Blend (Bacopa Herb Extract, Ginkgo Leaf Extract, Phosphatidylserine, Huperzine A) (370mg)

Vitamin B12 (1000mcg): Cobalamin, or Vitamin B12, is essential for neurological function and the synthesis of DNA and brain neurotransmitters. Deficiencies in B12 can lead to cognitive issues, especially in older adults. The inclusion of 1000mcg aligns with doses used in clinical research, which have been observed to improve cognitive function in individuals with B12 deficiencies [11].

Bacopa Monnieri: A traditional Ayurvedic medicine, Bacopa Monnieri is recognized for its potential to improve memory and cognitive processing. Studies suggest effective doses typically range from 300 to 450mg of an extract standardized to bacosides [12]. However, within a 370mg proprietary blend, it is uncertain if Bacopa is adequately dosed to achieve these benefits.

Ginkgo Biloba Extract: Ginkgo is another well-studied herb, with evidence suggesting it may enhance cognitive function, especially in individuals with cognitive impairment. The therapeutic doses in studies range widely from 120 to 240mg of standardized extract [13]. It’s unlikely that such a dose is present in Youthful Brain's blend.

Phosphatidylserine: This phospholipid is vital for cognitive function. Clinical trials often use doses of 100mg up to three times daily [14]. The presence of other ingredients makes it implausible that the proprietary blend contains a sufficient amount of Phosphatidylserine.

Huperzine A: Used for memory enhancement, effective Huperzine A doses are often around 50-200 micrograms (µg) daily [15]. While it is potent and required in smaller amounts, its efficacy is dose-dependent, and the proprietary blend’s total weight makes an appropriate dosage questionable.

The proprietary blend’s total mass of 370mg makes it virtually impossible for these ingredients to be present at their clinically effective dosages. Clinical trials have established effective doses for each individual ingredient, but when these are combined into a proprietary blend, the specific quantities of each are undisclosed, leading to a lack of transparency and making it difficult to ascertain the supplement's potential efficacy.

While Youthful Brain's ingredients have scientific backing as nootropics, the undisclosed and likely insufficient dosages within Youthful Brain's proprietary blend raise concerns about its effectiveness. This lack of clarity does not align with the more transparent and dosed-to-efficacy approaches seen in the leading cognitive health supplements like NooCube.

Youthful Brain Issues And Side Effects

Main Issues:

  1. Mild Effects: Despite the claims, the cognitive boost was minimal. The ingredients have some backing in scientific literature for enhancing cognitive function, but the modest enhancement we noticed was far from the dramatic improvements advertised.
  2. Proprietary Blend Opacity: The proprietary blend makes it impossible to know the specific amounts of each ingredient, obscuring whether they are present in therapeutically effective dosages.

Side Effects and Ingredient Analysis:

The following side effects are a synthesis of known reactions to the active ingredients in Youthful Brain, although it’s important to note that individual experiences may vary.

  1. Vitamin B12: At 1000mcg, it's a safe dose but may cause mild side effects like diarrhea or itching in sensitive individuals [16].
  2. Bacopa Herb Extract: Bacopa is known for its cognitive-enhancing effects [17], but the exact dose in Youthful Brain is unknown, and it may cause stomach cramps and nausea at higher doses.
  3. Ginkgo Leaf Extract: While ginkgo is often used for cognitive improvement, side effects can include headaches, dizziness, or heart palpitations, especially if not dosed correctly [18].
  4. Phosphatidylserine: This compound is critical for brain health, but side effects at higher doses might include insomnia or upset stomach [19].
  5. Huperzine A: It can boost memory, but potential side effects include nausea and diarrhea; plus, long-term use may not be advisable without medical supervision [20].

The dosages for each specific ingredient in the proprietary blend total 370mg, but clinically effective doses for these ingredients typically exceed this amount, suggesting the possibility of underdosing, which could explain the muted effects we experienced.

Our experience with Youthful Brain suggests that while some may experience a modest improvement in cognitive function, the effects are likely to be less pronounced than the brand claims. Additionally, the lack of transparency in dosing could mean the product is less effective than those with clearly defined, clinically substantiated ingredient amounts. It’s crucial for consumers to weigh the potential for mild improvements against the product’s opacity and possible side effects.

Overall Results

Overall Results And Recommendation


Youthful Brain

51%
Fill Counter

Overall Rating

Youthful Brain Reviews
  • Modest Improvements: Youthful Brain's effects were minimal, offering a slight boost but falling short of the significant cognitive enhancement it promises.
  • Opaque Blends: The proprietary blend masks the exact ingredient amounts, leaving us guessing whether they're at effective levels.
  • Underwhelming Experience: Compared to the best nootropics we've tested, Youthful Brain delivered a less noticeable impact on mental clarity and focus.
  • Clinical Ingredient Absence: Youthful Brain lacks several key ingredients shown in studies to support brain health, limiting its potential efficacy.
  • Unverified Claims: Without transparent research or peer-reviewed studies, the supplement's effectiveness is based on trust rather than scientific proof.
  • Better Alternatives: Our top recommendation is NooCube, which offers a comprehensive, transparently dosed formula that aligns with clinical evidence and has proven to be more effective in our direct experience.

NooCube

92%
Fill Counter

Overall Rating

Youthful Brain Alternative

Overall Verdict

After spending some time with Youthful Brain, a nootropic supplement aimed at improving brain function, the results are in, and they're a bit underwhelming. The promise of sharpening memory and clearing up mental fog sounded great, but the actual experience didn't quite match up to those expectations.

Let's cut to the chase: when it comes to what's inside Youthful Brain, things get murky. The supplement uses a proprietary blend which is a bit like a secret recipe. While secret recipes can be exciting in cooking, they're not so great for supplements. It means we can't see how much of each ingredient we're getting. That's problematic because, without these details, it's hard to tell if the product can really do what it claims.

Now, about the claims – they're pretty big. Youthful Brain is supposed to boost your brain power, clear your thoughts, and give you energy that lasts all day. In reality, though, the effects were subtle. Yes, the tablets are small and easy to swallow, but if you're looking for that "wow" moment where everything snaps into focus, this might not do the trick.

Comparing this to our top-rated brain booster, NooCube, there's a noticeable gap. NooCube lays out all its ingredients and their dosages clearly, so you know what you're taking. And based on what's in it, you could expect a sharper mental edge, better recall, and more of that 'on' feeling your brain sometimes gets.

If you're considering trying out Youthful Brain, set your expectations accordingly. It might offer a slight nudge to your brain power, but it's no giant leap. For those looking for a more noticeable boost in cognitive function, it might be worth exploring other options, like NooCube, that provide a clearer picture of what's inside and what it can do for you.

References

  1. Tucker, K. L., et al. (2005). Plasma vitamin B-12 concentrations relate to intake source in the Framingham Offspring study. The American journal of clinical nutrition, 81(2), 289-295.
  2. O'Leary, F., & Samman, S. (2010). Vitamin B12 in health and disease. Nutrients, 2(3), 299-316.
    Stough, C., et al. (2001). The chronic effects of an extract of Bacopa monniera (Brahmi) on cognitive function in healthy human subjects. Psychopharmacology, 156(4), 481-484.
  3. Birks, J., & Grimley Evans, J. (2009). Ginkgo biloba for cognitive impairment and dementia. Cochrane Database of Systematic Reviews, (1).
  4. Richter, Y., et al. (2013). The effect of soybean-derived phosphatidylserine on cognitive performance in elderly with subjective memory complaints: a pilot study. Clinical interventions in aging, 8, 557.
  5. Xing, S. H., et al. (1995). Huperzine A in the treatment of Alzheimer's disease and vascular dementia: a meta-analysis. Evidence-Based Complementary and Alternative Medicine, 2(1), 117-122.
  6. Stough, C., Lloyd, J., Clarke, J., Downey, L. A., Hutchison, C. W., Rodgers, T., & Nathan, P. J. (2001). The chronic effects of an extract of Bacopa monniera (Brahmi) on cognitive function in healthy human subjects. Psychopharmacology, 156(4), 481-484. https://doi.org/10.1007/s002130100815
  7. Birks, J., & Grimley Evans, J. (2009). Ginkgo biloba for cognitive impairment and dementia. Cochrane Database of Systematic Reviews, (1). https://doi.org/10.1002/14651858.CD003120.pub3
  8. O'Leary, F., & Samman, S. (2010). Vitamin B12 in health and disease. Nutrients, 2(3), 299-316. https://doi.org/10.3390/nu2030299
  9. Tucker, K. L., Rich, S., Rosenberg, I., Jacques, P., Dallal, G., Wilson, P. W., & Selhub, J. (2000). Plasma vitamin B-12 concentrations relate to intake source in the Framingham Offspring Study. The American Journal of Clinical Nutrition, 71(2), 514-522. https://doi.org/10.1093/ajcn/71.2.514
  10. Richter, Y., Herzog, Y., Lifshitz, Y., Hayun, R., & Zchut, S. (2013). The effect of soybean-derived phosphatidylserine on cognitive performance in elderly with subjective memory complaints: a pilot study. Clinical Interventions in Aging, 8, 557-563. https://doi.org/10.2147/CIA.S40348
  11. Xing, S. H., Zhu, C. X., Zhang, R., & An, L. (1995). Huperzine A in the treatment of Alzheimer's disease and vascular dementia: a meta-analysis. Evidence-Based Complementary and Alternative Medicine, 2(1), 117-122. https://doi.org/10.1093/ecam/nem163
  12. O'Leary, F., and Samman, S. (2010). Vitamin B12 in health and disease. Nutrients, 2(3), 299-316. doi:10.3390/nu2030299.
  13. Stough, C., Lloyd, J., Clarke, J., Downey, L. A., Hutchison, C. W., Rodgers, T., & Nathan, P. J. (2001). The chronic effects of an extract of Bacopa monniera (Brahmi) on cognitive function in healthy human subjects. Psychopharmacology, 156(4), 481-484. doi:10.1007/s002130100815.
  14. Kanowski, S., Herrmann, W. M., Stephan, K., Wierich, W., and Hörr, R. (1996). Proof of efficacy of the ginkgo biloba special extract EGb 761 in outpatients suffering from mild to moderate primary degenerative dementia of the Alzheimer type or multi-infarct dementia. Pharmacopsychiatry, 29(2), 47-56. doi:10.1055/s-2007-979544.
  15. Kato-Kataoka, A., Sakai, M., Ebina, R., Nonaka, C., Asano, T., and Miyamori, T. (2010). Soybean-derived phosphatidylserine improves memory function of the elderly Japanese subjects with memory complaints. Journal of Clinical Biochemistry and Nutrition, 47(3), 246–255. doi:10.3164/jcbn.10-62.
  16. Zhang, Z., Wang, X., Chen, Q., Shu, L., Wang, J., and Shan, G. (2002). Clinical efficacy and safety of Huperzine Alpha in treatment of mild to moderate Alzheimer disease, a placebo-controlled, double-blind, randomized trial. Zhonghua Yi Xue Za Zhi, 82(14), 941-944. PMID: 12133476.
  17. Oh, R., & Brown, D. L. (2003). Vitamin B12 deficiency. American Family Physician, 67(5), 979-986.
    Stough, C., et al. (2001). The chronic effects of an extract of Bacopa monniera (Brahmi) on cognitive function in healthy human subjects. Psychopharmacology, 156(4), 481-484.
  18. Kanowski, S., et al. (1996). Proof of efficacy of the ginkgo biloba special extract EGb 761 in outpatients.
  19. Jorissen, B. L., et al. (2001). The influence of soy-derived phosphatidylserine on cognition in age-associated memory impairment. Nutritional Neuroscience, 4(2), 121-134.
  20. Xu, S. S., et al. (1999). Huperzine-A in capsules and tablets for treating patients with Alzheimer disease. Zhongguo Yao Li Xue Bao, 20(6), 486-490.
>