Since ancient times, honey has been considered a health ingredient. And it has always been employed, in peoples’ medicine, to prevent and treat various forms of ailments and diseases. A brief review of the scientific literature confirms the soundness of traditional knowledge.
Honeys and honeydew
Honeys are produced and accumulated by honey bees. From the nectar, flower or secretions of plants of different botanical species. (1) Products are traditionally divided into monofloral and millefiori. Where some ‘monoflorals’, according to some sources, would be preferable to the latter in relation to specific health properties. (2)
Honeydew, produced by insect secretion, has a higher content of protein, minerals and phenolic substances. It contains less simple sugars and more complex carbohydrates and is considered even more effective than honey in biological and health benefit properties. (3)
Studies on honeys, in Italy and around the world
Environmental conditions-in addition to botanical species-have a strong influence on the characteristics of honey. Numerous studies have evaluated the influence of geographical origin on the organoleptic and health properties of the honeys analyzed. The most important research has been conducted on products from countries where beekeeping is most prominent. (4) And so:
– acacia, sulla, tree of paradise, thyme, orange, millefiori, chestnut, and savory honeys have been studied in Italy. The last three have demonstrated more important health effects, (5)
– in Spain, the properties of honeys, honeys and their blends, obtained locally, were evaluated. Finding on honeydew the best results, (6)
– in Romania the honeys analyzed came from mint, raspberry, sunflower, turnip, and thyme flowers. In addition to millefiori. Darker honeys, mint honey in particular, have shown the best health properties. Next, raspberry, thyme and mixed-flower honeys, (7)
– in Poland, the importance of the cultivation method was also evaluated. Comparison of organically and conventionally grown honeys shows the superiority of the former. As already verified on other food categories, (8)
– New Zealand produces Manuka honey (from Leptospermum scoparium), which is recognized for important beneficial properties, particularly its antibacterial action,
– honeys from Borneo, Gelam (from Melaleuca cajuputi, in Southeast Asia and Australia) and Tualang (from Koompassia excelsa, in Malaysia Indonesia Thailand and the Philippines) are also noteworthy. Tualang’s, by the way, was found to excel in the amount of antioxidants and effectiveness against free radicals. (9)
Fig. 1. Difference in polyphenol composition of honeys from different countries of the world
Honey and health
Numerous studies have been conducted on honey and health. The leading role is attributed to its phenolic compounds, which are able to exert an effective antioxidant action. Useful among other things to help prevent various chronic-degenerative diseases. (10)
The antimicrobial properties of honey have been known since time immemorial. The antiviral action is particularly interesting, especially on the H1N1 influenza virus, due to the action of acacia and Manuka honey and their synergistic effect with antiviral drugs. (11)
The growth of pathogenic bacteria and fungi is inhibited by the phenols present and other compounds with antimicrobial action. (12)
Added to the antibacterial capacity is the ability to help heal wounds. In fact, honey stimulates tissue regrowth, reducing the formation of edema and scarring. (13)
Contributions to disease prevention
Chemoprevention. Honey has been found to intervene in the three stages of cancer development (initiation, promotion and progression). By activating defense systems with respect to cancer diseases, it helps to enhance innate defenses. These effects have been demonstrated through special studies on numerous cancer cell lines, with often positive results. (14)
Fig. 2. Effects of honey in chemoprevention
Blood glucose. Significant benefits have also been observed in relation to both forms of diabetes (type 1 and type 2). Due to the presence of polyphenols with antioxidant action, which act on the oxidative stress strongly related to this disease. Clinical studies have also shown honey’s ability to reduce postprandial blood glucose. (15)
Polyphenols
The presence of polyphenols-in association with certain vitamins in the food, such as vitamin C-has been shown to be effective in protecting the heart system. Due to its abilities to reduce platelet activity, protect LDL cholesterol (so-called bad cholesterol) from oxidation, improve coronary vasodilation. (16)
Polyphenols help strengthen the immune system, as noted. And they exert a protective action against the nervous system as well, due to their ability to reduce oxidative stress. Thus hindering the action of neurodegenerative diseases involved in aging processes. (17)
Respiratory system
Soothing a cough with the help of honey has been a common practice for centuries. Its use is also indicated in cases of asthma, a condition of breathing difficulty due to chronic inflammation of the lower respiratory tract, often associated with allergies. (18) Allergic rhinitis can then be alleviated with the help of large doses of honey (1g/kg body weight for 4 weeks), in conjunction with specific medications. (19)
Athletes can derive important benefits from consuming such food. In fact, physical activity can promote the onset of oxidative stress to which reduced sports performance results. (20) And iI regular consumption of honey-the Manuka honey, in particular, over a three-week period-has demonstrated the capacity for a strong reduction of oxidation in muscles. (21)
Honey, gut and microbiome
The microbiome exerts a key role in individual immunomodulation, that is, on the immune system. And honey, like other foods, also contributes to the composition and concentration of ‘health-friendly’ bacteria in the gut microbiota. (22)
The carbohydrates in honey, in particular, can selectively stimulate the growth of Bifidobacteria. A genus of bacteria involved in the balance of gut flora due to its ability to lower the pH in the intestine and hinder potentially harmful bacteria. (23) As well as alleviating some gastrointestinal diseases of bacterial origin.
Infant gastroenteritis, among others, show a reduction in the period of diarrhea and facilitation of recovery-because of increased rehydration capacity-thanks to this valuable food. (24)
Fig. 3 Examples of some of the many activities of honey and their health benefits
The safety of honey
Honey has several health benefits and yet is subject to some vulnerabilities. Therefore, it is recommended that honeys be chosen that come from reliable operators, when they are even small beekeepers.
The high concentration of sugars and the presence of antimicrobial substances prevent the growth of harmful microorganisms in this product. And yet, even this food is exposed to the risk of contamination by resistant bacterial spores, (25) such as Clostridium botulinum. Botulinum toxins in honey are susceptible to children in particular. (26)
Then there are certain fungi-yeasts and molds mainly-that can tolerate high sugar concentrations and thus develop in the product. (27) As well as some toxic compounds, which mostly result from environmental and process contamination. (28) Among the process contaminants-which are formed as a result of poor and prolonged storage of honey at too high temperatures, even after purchase-is 5-HMF (5-hydroxymethylfurfural). (29) The ‘HMF’, in the jargon, is therefore considered an ‘old-age index’ of the product.
Pollution, pesticides, fraud
The environment is, as obvious, a potential source of contaminants, which can pollute the flowers and thus the pollen used for honey production. Heavy metals, in particular, are present in the air, water and soil and can also residue in plants involved in honey production, causing potential toxic and carcinogenic effects. (30)
Pesticides
, herbicides, fungicides , and other agrotoxics can in turn residue in the plant, and so in honey, through pollen. (31) As well as accumulating in the wax used in beehives. (32) It is no coincidence that organic wax, which is essential to the production of organic honey, costs twice as much as ‘conventional’ wax.
Codex Alimentarius-and so does European legislation (dir. 2001/110/EC as amended)-prohibits any alteration of honey with any substance foreign to its natural composition. (33) The use of corn syrups, beet molasses, sucrose are the most common frauds. (34) Moreover, official public controls in Italy are very effective, as noted above. (35)
Storage and note for vegans
Because it is a live food, honey must be stored away from light and prolonged exposure to temperatures above 25 degrees. therefore it is recommended to keep a low Shelf Life by reducing the number of specimens and keeping the stock in a dark and cool place.
It is also true that honey is processed by the bee, but the bee processes nectar by adding only the enzyme glucose oxidase. Which, due to its high bacteriostatic power, allows the product to remain stable and prevent contamination. This enzyme, together with glucose and water (nectar), develops H2O2. That is, hydrogen peroxide. Creating an inhospitable environment for microorganisms as well, as seen.
Dario Dongo and Andrea Adelmo Della Penna
Notes
(1) Consonni R. et al. (2015) Recent developments in honey characterization. RSC Advances, 5(73):59696-59714, https://doi.org/10.1039/C5RA05828G
(2) Kumar P. et al. (2010) Honey collected from different floras of Chandigarh Tricity: A comparative study involving physicochemical parameters and biochemical activities. J. Diet. Suppl. 7:303-313, doi: 10.3109/19390211.2010.508034
(3) Tischer Seraglio et al. (2019) An overview of physicochemical characteristics and health-promoting properties of honeydew honey. Food Research International 119:44-66, https://doi.org/10.1016/j.foodres.2019.01.028
(4) Puscas et al. (2013) Application of a newly developed and validated high-performance thin-layer chromatographic method to control honey adulteration. J. Chromatogr. AT 1272:132-135, https://doi.org/10.1016/j.chroma.2012.11.064
(5) Pichichero et al. (2009) Chacterisation of the phenolic and flavonoid fractions and antioxidant power of Italian honeys of different botanical origin. J. Sci. Food Agric. 89:609-616, doi:10.1002/jsfa.3484
(6) Pérez et al. (2007) Amino acid composition and antioxidant capacity of spanish honeys. J. Agric. Food Chem. 55:360-365, doi: 10.1021/jf062055b
(7) Pauliuc et al. (2020) Antioxidant activity, total phenolic content, individual phenolics and physicochemical parameters suitability for Romanian honey authentication. Foods 9:306, doi:10.3390/foods9030306
(8) Halagarda et al. (2020) Antioxidant activity and phenolic profile of selected organic and conventional honeys from Poland. Antioxidants 9:44, doi:10.3390/antiox9010044
(9) Khalil et al. (2011) Phenolic acid composition and antioxidant properties of Malaysian honeys. Journal of Food Science 76:C921-928, doi: 10.1111/j.1750-3841.2011.02282.x
(10) Cianciosi et al. (2018) Phenolic compounds in honey and their associated health benefits: a review. Molecules 23:2322, doi:10.3390/molecules23092322
(11) Watanabe et al. (2014) Anti-influenza viral effects of honey in vitro: Potent high activity of Manuka honey. Med. Res. Arch. 45:359-365, doi:10.1016/j.arcmed.2014.05.006
(12) Agbaje et al. (2006) Conventional use of honey as antibacterial agent. Ann. Afr. Med. 2006, 5:79-81
(13) Saha et al. (2012) The role of honey in healing of bedsores in cancer patients. South Asian J. Cancer 1:66-71, doi: 10.4103/2278-330X.103714
(14) Orsolic et al. (2003) Influence of honey bee products on transplantable murine tumors. Vet. Comp. Oncol. 1:216-226, doi: 10.1111/j.1476-5810.2003.00029.x
(15) Folli et al. (2011) The role of oxidative stress in the pathogenesis of type 2 diabetes mellitus micro- and macrovascular complications: Avenues for a mechanistic-based therapeutic approach. Curr. Diabetes Rev. 7:313-324
(16) Khalil et al. (2010) The Potential Role of Honey and its Polyphenols in Preventing Heart Diseases: A Review. Afr. J. Tradit. Complement. Altern. Med. 7:315-321, doi: 10.4314/ajtcam.v7i4.56693
(17) Syarifah-Noratiqah et al. (2018) Natural polyphenols in the treatment of Alzheimer’s Disease. Curr. Drug Targets 19:927-937, doi: 10.2174/1389450118666170328122527
(18) Bâcvarov (1970) Treatment of chronic bronchitis and bronchial asthma with honey. Ther. Ggw. 109:260-268
(19) Asha’ari et al. (2013) Ingestion of honey improves the symptoms of allergic rhinitis: Evidence from a randomized placebo-controlled trial in the East Coast of Peninsular Malaysia. Ann. Saudi Med. 33:469-475, doi: 10.5144/0256-4947.2013.469
(20) St-Pierre et al. (2002) Topology of superoxide production from different sites in the mitochondrial electron transport chain. J. Biol. Chem. 277:44784-44790
(21) Jurcau et al. (2017) Effect of Manuka honey administration on malondialdehyde, in intense exercise. Palest. Third Millenn. Civ. Sports 18:201-205, doi: 10.26659/pm3.2017.18.4.201
(22) Jiang et al. (2020) Phenolics and carbohydrates in buckwheat honey regulate the human intestinal microbiota. Evidence-Based Complementary and Alternative Medicine Article ID 6432942 1-11, https://doi.org/10.1155/2020/6432942
(23) Shin et al. (2005) Carbohydrate composition of honey from different floral sources and their influence on growth of selected intestinal bacteria: an in vitro comparison. Food Research International 38(6):721-728, https://doi.org/10.1016/j.foodres.2005.01.007
(24) Blasa et al. (2006) Raw Millefiori honey is packed full of antioxidants. Food Chemistry 97(2):217-222, https://doi.org/10.1016/j.foodchem.2005.03.039
(25) Abdulla et al. (2012) Infant botulism following honey ingestion. BMJ Case Rep. 2012, doi: 10.1136/bcr.11.2011.5153
(26) Dembek et al. (2007) Botulism: Causes, effects, diagnosis, clinical and laboratory identification, and treatment modalities. Disaster Med. Public Health Prep. DMPHP 1:122-134, doi: 10.1097/DMP.0b013e318158c5fd
(27) Sinacori et al. (2014) Cultivable microorganisms associated with honeys of different geographical and botanical origin. Food Microbiology, 38:284-294, https://doi.org/10.1016/j.fm.2013.07.013
(28) Islam et al. (2014) Toxic compounds in honey. J. Appl. Toxicol. 34:733-742, doi: 10.1002/jat.2952
(29) Shapla et al. (2018) 5-Hydroxymethylfurfural (HMF) levels in honey and other food products: Effects on bees and human health. Chem. Cent. J. 12:35, doi: 10.1186/s13065-018-0408-3
(30) Johnson (2014) Honey bee toxicology. Annual Review of Entomology 60:415-434. https://doi.org/10.1146/annurev-ento-011613-162005
(31) Rial-Otero et al. (2007) Chromatographic-based methods for pesticide determination in honey: An overview. Talanta, 71(2):503-514. https://doi.org/10.1016/j.talanta.2006.05.033
(32) Jakob A. Shimshoni, Roy Sperling, Shimon Barel. (2019). Pesticide distribution and depletion kinetic determination in honey and beeswax: Model for pesticide occurrence and distribution in beehive products.
PLoS One. 2019; 14(2): e0212631. doi: 10.1371/journal.pone.0212631
(33) Codex Alimentarius Commission (2001). Codex Standard for Honey CODEX STAN. 12-1981
(34) Ribeiro et al. (2014) Detection of honey adulteration of high fructose corn syrup by low field nuclear magnetic resonance (LF 1H NMR). Journal of Food Engineering, 135:39-43, https://doi.org/10.1016/j.jfoodeng.2014.03.009
(35) Chinese honey and fake news.V. https://www.foodagriculturerequirements.com/archivio-notizie/domande-e-risposte/miele-cinese-risponde-l-avvocato-dario-dongo
Dario Dongo, lawyer and journalist, PhD in international food law, founder of WIISE (FARE - GIFT - Food Times) and Égalité.
Graduated in Food Technologies and Biotechnologies, qualified food technologist, he follows the research and development area. With particular regard to European research projects (in Horizon 2020, PRIMA) where the FARE division of WIISE Srl, a benefit company, participates.
