Apple Polyphenols

 

The humble apple has an impressive history in Western art, literature and medicine. In mythology, the Norse gods owed their immortality to apples. The Arabian Nights even features a magic apple capable of curing all human diseases. Then, first appearing in print in 1866, was the proverb that “an apple a day keeps the doctor away.”1 Aside from art and literature, the medicinal properties of apples are well documented within the biomedical literature. For example, apple consumption has been the subject of quite a few studies on colorectal cancer risk reduction.2-4 This article will focus on a specific component of apples, their polyphenols and the health-promoting benefits they provide.

Background of Apple Polyphenols

Since much of the research on apple polyphenols (AP) have been conducted on ApplePhenon (BGG), a patented, proprietary polyphenol extract produced from wild unripe apple fruit from the central Asia region, this article will primarily focus on that extract.

Providing about 70 percent polyphenols by spectrophotometric analysis, AP have been fully characterized and possess a unique phytochemical profile, with about 12 percent of flavanol monomers (catechin and epicatechin) and a high content of oligomeric proanthocyanidins. These are some of the same groups of antioxidant polyphenols found in green tea and grapeseed extract.5 Even so, when compared to green tea and grapeseed extracts, AP has significantly greater antioxidant activity as indicated in ORAC (oxygen radical absorbance capacity) testing.6

Furthermore, animal research indicates that oligomeric procyanidins in AP are easily absorbed into the blood, possibly more so than other polyphenol products.7

Now, let’s take a look at the human clinical research on AP for weight and glucose management, cardiovascular protection and other benefits.

Weight & Glucose Management

A randomized double-blind, placebo-controlled study8 was conducted to evaluate the safety and the efficacy of high intake and long-term AP intake on normal weight or moderate obesity subjects (138 subjects for long-term intake, 53 subjects for high intake). In the long-term intake trial, the subjects were divided into three groups: 1) drinking beverage with 600 mg AP, 2) drinking beverage with 300 mg AP or 3) drinking beverage without AP. Subjects were given 340 g of beverage daily for 12 weeks. In the high intake trial, the subjects were divided into two groups: 1) drinking beverage with 600 mg AP, or 2) drinking beverage without AP. Subjects were given three times as much of the beverage a day for four weeks. The results were significant decreases of body weight and body fat, especially visceral fat, which were observed in the long-term intake in the group 600 mg AP beverage group. There were no clinical problems in the blood examinations and physical examinations. No adverse reactions were observed. These results suggested the efficacy and the safety of beverages with apple polyphenols.

Similar to the previous study, another randomized, double-blind, placebo-controlled study9 was performed to evaluate the safety of high AP intake and the efficacy of a long-term AP intake in moderately underweight to moderately obese subjects (long-term intake: 94 subjects; excessive intake: 30 subjects). For each trial, the subjects were divided into the following two groups: 1) a group that drank beverages with 600 mg AP (the apple group) and a group that drank beverages without AP (the placebo group). For the long-term intake trial, the subjects were given 340 g of the beverage each day for 12 weeks. For the excessive intake trial, the subjects were given 1,020 g of the beverage each day for four weeks. Results showed that the visceral fat area (VFA) of subjects in the long-term apple group decreased significantly by the 8- and 12-week marks (week 8: p<0.05; week 12: p< 0.01) compared to the baseline (week 0). The degree of change in VFA experienced by subjects in the apple group compared to those in the placebo group was significantly lower by the eight- and 12-week marks (p < 0.01). Of particular interest was that those subjects who started with a high VFA experienced the decrease, with those who started with a normal VFA had no significant change. No adverse reaction was observed in either trial. These results demonstrated the efficacy and the safety of the beverage with apple polyphenols.

In a human study,10 the unripe apples were pressed to obtain apple pomace, which was then processed, dried and milled to prepare apple powder (providing polyphenols). In six healthy volunteers, ingestion of the apple powder reduced postprandial (i.e. after eating) glucose response at 15 to 30 min by approximately two-fold (P < 0.05) and increased urinary glucose excretion during the 2- to 4-h interval of the OGTT by fivefold (P < 0.05). The authors of this study concluded that the apple powder could be used as a health-promoting natural product for the reduction of postprandial glycaemia and to improve the health of patients with diabetes. Similar results in reducing glucose absorption were also seen in another study.11

Cardiovascular Protection

A randomized, double-blind, placebo-controlled, parallel arm, clinical study12 was conducted using 46 healthy male and female subjects who had slightly elevated cholesterol levels in their serum to examine the effects of AP (ApplePhenon, BGG) for improving serum cholesterol concentrations in rats and humans. The total period of this study was four weeks and blood samples were obtained at week 0 and week 4. Results were that total cholesterol levels of the AP groups decreased significantly and dose-dependently compared with that of the control group. LDL-cholesterol also decreased significantly, and HDL-cholesterol increased. No abnormalities were detected in biochemical examinations of any of the subjects during the test period. Researchers concluded that the AP is useful for improving serum cholesterol concentrations, and that such improvement is expected to decrease the risk of atherosclerosis for people with a slightly elevated total cholesterol level.

Two years later, another randomized double-blind, placebo-controlled study13 was published. This one had 71 moderately obese male and female subjects with a body mass index ranging from 23 to 30 to evaluate the efficacy of 12-week intake of 1) AP (ApplePhenon, BGG, 600 mg/day), 2) hop bract polyphenol (600 mg/day), and 3) placebo. The results were that 12-week ingestion of AP significantly decreased total cholesterol and LDL-cholesterol levels (LDL decreased by 16.13 mg/dl, p<0.05). The effects of AP were more marked than those of the hop bract polyphenol-containing capsules. The visceral fat area and the level of adiponectin in the group administered apple polyphenols improved in comparison with the control group. Blood and physical examinations revealed no clinical problems, and no adverse reactions were observed during the ingestion period. These results demonstrate that AP regulate fat metabolism in healthy subjects with relatively high body mass index.

Pancreatic lipase is the enzyme that breaks down fats, allowing their triglycerides to be absorbed. A study14 conducted in mice and humans demonstrated that the oligomeric procyanidins contained in AP inhibited triglyceride absorption by inhibiting pancreatic lipase activity in mice and humans.

Other Benefits

In addition to AP’s benefits for weight and glucose management, and cardiovascular protection, there are a range of other benefits associated with their use. Here are a few of those benefits.

Dental Care

AP (ApplePhenon, BGG) can interfere with the dental bacteria Streptococci mutans and Porphyromonas gingivalis, thereby helping to prevent dental plaque formation. A clinical study with 20 19- to 20-year-old women who rinsed their mouths with 10 mL of AP solution (0.5 mg/mL) three to five times a day for three days showed significant decrease of dental plaque formation. Chewing gum containing AP can also inhibit methanethiol (main cause of bad breath) production after chewing for five minutes at low dose of 0.024 percent AP.15

Allergy

A double-blind comparative study16 was conducted on cedar pollinosis patients in order to evaluate the treatment efficacy of 500 mg AP, administered once daily for 12 weeks, starting about two weeks prior to cedar pollen dispersion. Pollinosis symptoms during the study were evaluated according to the classification in the guidelines for allergic rhinitis diagnosis and treatment. The results show that the sneezing score was significantly lower for the AP group than with the placebo group during the early period of pollen dispersion and during the main dispersion period. In addition, no adverse reactions were induced by AP during the study. These results suggest that AP may alleviate the symptoms of cedar pollinosis.

Another randomized, double blind and placebo-controlled clinical trial17 was conducted to assess the effectiveness of AP (ApplePhenon, BGG) in 33 patients (aged 15 to 65 years) with persistent allergic rhinitis. Patients were divided into three groups: 1) 50 mg AP per bottle for the low-dose group, 2) 200 mg per bottle for the high-dose group, and 3) a sham drink that did not contain apple polyphenols for the control group. The results showed significant improvements in sneezing attacks (P<.05) and nasal discharge (P<.01) in the high-dose group and in sneezing attacks (P<.05) in the low-dose group. Compared with the control group, an improvement was observed in sneezing attacks and nasal discharge in many patients of the AP-treated groups. In terms of intranasal findings, a significant improvement was observed in swelling of the nasal turbinate in the low-dose group (P<.05). The percentage of patients who showed an improvement in swelling of the nasal turbinate was higher in the AP-treated groups. Researchers concluded that AP are effective in alleviating symptoms of persistent allergic rhinitis.

Skin Care

A pilot study18 was conducted to evaluate the antiallergic effect of AP in 24 patients with atopic dermatitis (eczema). AP (ApplePhenon, BGG) given to the patients at oral doses of 10 mg/kg of body weight per day for eight weeks reduced the inflammation, lichenification (i.e. thick, leathery patches of skin in response to excessive itching or rubbing), cracking, itching and sleep disturbance. Itching and sleep disturbance scores were significantly decreased compared with the control group even after two weeks. The results suggest that AP has an anti-allergic effect and that its use improved the symptoms of atopic dermatitis.

In another three-arm study19 with 65 female subjects, both low dosage (300 mg/day) and high dosage (600 mg/day) AP (ApplePhenon, BGG) treated groups showed obvious skin whitening effects compared with placebo group after a 10-week administration.

Additionally, research has been published demonstrating the effectiveness of AP in a variety of other areas, including (but not limited to) digestion and elimination, immunity, athletic performance, muscle, bone and joint health, neuroprotection, liver protection and lung protection for smokers—but that’s the topic for another article.

Conclusion

AP is naturally composed of flavanol monomers (catechin and epicatechin) and oligomeric proanthocyanidins. AP has greater antioxidant properties than green tea, grapeseed extract and several other natural antioxidants. Much of the human clinical research on AP has been conducted on ApplePhenon (BGG), a proprietary, patented material. The research has demonstrated safety and efficacy for weight and glucose management, cardiovascular protection, dental health, allergy, skin care and more.

References:

1 Rupp R. The History of the “Forbidden” Fruit. National Geographic. Published July 22, 2014. Retrieved April 26, 2019 from www.nationalgeographic.com/people-and-culture/food/the-plate/2014/07/22/history-of-apples/.

2 Jedrychowski W, Maugeri U. An apple a day may hold colorectal cancer at bay: recent evidence from a case-control study. Rev Environ Health. 2009 Jan-Mar;24(1):59-74.

3 Jedrychowski W, Maugeri U, Popiela T, Kulig J, Sochacka-Tatara E, Pac A, Sowa A, Musial A. Case-control study on beneficial effect of regular consumption of apples on colorectal cancer risk in a population with relatively low intake of fruits and vegetables. Basic Clin Pharmacol Toxicol. 2009 Mar;104(3):262-71.

4 Deneo-Pellegrini H, De Stefani E, Ronco A. Vegetables, fruits, and risk of colorectal cancer: a case-control study from Uruguay. Nutr Cancer. 1996;25(3):297-304.

5 Yanagida A, Shoji T, Kanda T. Characterization of polymerized polyphenols by size-exclusion HPLC. Biosci Biotechnol Biochem. 2002 Sep;66(9):1972-5.

6 ApplePhenon Polyphenols. BGG. 2017:8pgs.

7 Shoji T, Masumoto S, Moriichi N, Akiyama H, Kanda T, Ohtake Y, Goda Y. Apple procyanidin oligomers absorption in rats after oral administration: analysis of procyanidins in plasma using the porter method and high-performance liquid chromatography/tandem mass spectrometry. J Agric Food Chem. 2006 Feb 8;54(3):884-92.

8 Akazome Y, Kanda T, Ohtake Y, et al. Evaluation of safety of excessive intake and efficacy of long term intake of beverage containing polyphenols derived from apples. Jpn Pharmacol Ther. 2005;33(9):893-911.

9 Akazome Y, Kametani N, Kanda T, Shimasaki H, Kobayashi S. Evaluation of safety of excessive intake and efficacy of long-term intake of beverages containing apple polyphenols. J Oleo Sci. 2010;59(6):321-38.

10 Makarova E, Górnaś P, Konrade I, Tirzite D, Cirule H, Gulbe A, Pugajeva I, Seglina D, Dambrova M. Acute anti-hyperglycaemic effects of an unripe apple preparation containing phlorizin in healthy volunteers: a preliminary study. J Sci Food Agric. 2015 Feb;95(3):560-8.

11 Schulze C, Bangert A, Kottra G, Geillinger KE, Schwanck B, Vollert H, Blaschek W, Daniel H. Inhibition of the intestinal sodium-coupled glucose transporter 1 (SGLT1) by extracts and polyphenols fromapple reduces postprandial blood glucose levels in mice and humans. Mol Nutr Food Res. 2014 Sep;58(9):1795-808.

12 Nagasako-Akazome Y, Kanda T, Ikeda M, Shimasaki H. Serum Cholesterol-Lowering Effect of Apple Polyphenols in Healthy Subjects. J Oleo Sci. 2005;54(3):143-151.

13 Nagasako-Akazome Y, Kanda T, Ohtake Y, Shimasaki H, Kobayashi T. Apple polyphenols influence cholesterol metabolism in healthy subjects with relatively high body mass index. J Oleo Sci. 2007;56(8):417-28.

14 Sugiyama H, Akazome Y, Shoji T, Yamaguchi A, Yasue M, Kanda T, Ohtake Y. Oligomeric procyanidins in apple polyphenol are main active components for inhibition of pancreatic lipase and triglyceride absorption. J Agric Food Chem. 2007 May 30;55(11):4604-9.

15 ApplePhenon Polyphenols. BGG. 2017:8pgs.

16 Kishi K, Saito M, Saito T, Kumemura M, Okamatsu H, Okita M, Takazawa K. Clinical efficacy of apple polyphenol for treating cedar pollinosis. Biosci Biotechnol Biochem. 2005 Apr;69(4):829-32.

17 Enomoto T, Nagasako-Akazome Y, Kanda T, Ikeda M, Dake Y. Clinical effects of apple polyphenols on persistent allergic rhinitis: A randomized double-blind placebo-controlled parallel arm study. J Investig Allergol Clin Immunol. 2006;16(5):283-9.

18 Kojima T, Akiyama H, Sasai M, Taniuchi S, Goda Y, Toyoda M, Kobayashi S. Anti-allergic effect of apple polyphenol on patients with atopic dermatitis: A pilot study. Allergology International (2000) 49: 69–73

19 ApplePhenon Polyphenols. BGG. 2017:8pgs.

Gene Bruno, MS, MHS, the dean of academics for Huntington College of Health Sciences, is a nutritionist, herbalist, writer and educator. For more than 30 years he has educated and trained natural product retailers and health care professionals, has researched and formulated natural products for dozens of dietary supplement companies, and has written articles on nutrition, herbal medicine, nutraceuticals and integrative health issues for trade, consumer magazines and peer-reviewed publications. He can be reached at gbruno@hchs.edu.