Ingredient Type: Metabolite
Also Known As: β-Carotene, Provitamin A
Plants and animals need nutrients to stay healthy. Each performs different, valuable functions in our body. Some functions are essential when in comparison with others. Essential nutrients are considered not to be produced in the body, requiring dietary supplementation to stay healthy. Vitamin A is considered an essential nutrient needed for immune function, vision, reproduction, and cellular communication. Some preformed vitamin A sources include; milk and eggs, while most dietary sources are found in green vegetables, orange, yellow vegetables, tomato products, and fruits. Beta-carotene remains an important provitamin A nutrient that is found in plant sources. One mcg RAE for beta-carotene is two mcg. 12 mcg dietary beta-carotene is needed to form the required vitamin A levels needed by the body to stay healthy.
Beta-carotene is a critical member of the carotenoid family produced in plants. It is the primary source of vitamin A in humans. The provitamin A role of beta-carotene gives the carotenoid several other vital functions in the body. Diet deficiencies have been associated with several anatomical and physiological deficiencies, such as those noted in xerophthalmia, blindness, and premature death.
Beta-carotene, known for its vibrant colors, was first discovered and isolated in 1831 by H. Wakenroder. However, it was not until 1907 that an empirical formula was established for beta-carotene, C40H56 by Willstatter and Mieg. The complete synthesis of the compound was achieved around 1950. Shortly after that, Roche started manufacturing and distributing it commercially. During the 1970s-1980s, much research was conducted to assess the usefulness and effectiveness of the food and pharmaceutical industries. Similar to today’s application of beta-carotene, starting in the early 80’s it was suggested this be taken to support cancer prevention, various diseases such as cystic fibrosis and arthritis, as well as an antioxidant (11).
WHAT DOES SCIENCE TELL US?
Beta-Carotene Might Improve Cognitive Function:
A randomized control trial conducted by Grodstein et al. (2007) revealed the role of beta carotene supplementation on cognitive function. The study’s goal was to uncover how beta-carotenoid can help reduce oxidative stress, which contributes to brain aging, hence decreased cognitive function. Cognitive testing was conducted on patients supplemented with different vitamins, including beta carotene. Five thousand nine hundred fifty-six older participants older than 65 were placed on 50 mg beta-carotene on varying days. Subsequently, an interview was conducted to evaluate general cognition, verbal memory, and categorical fluency. Out of the total participants, 1,904 were newly recruited within one year, while 4,052 others had already been in the program for 18 years. Based on a series of short term data from this study, beta-carotenoid supplementation has little effect on cognitive function. On the other hand, while assessing long-term data, it was observed that beta-carotene provides more beneficial cognitive effects (1).
In another study, researchers explored the role of vitamin E, vitamin C, and beta-carotene on cognitive function in a particular group of female participants. The study was focused on the fact that cardiovascular disorders tend to be typically associated with cognitive decline; hence, beta-carotene was studied with respect to these functions. The trial was conducted on women with clinically diagnosed cardiovascular disorders such as CVD or other associated CVD risk factors. The subjects were placed on 402 mg of vitamin E on alternate days, 50mg beta-carotene every other day, and vitamin C (500 mg) daily. The study was conducted over five years, with 2,824 women above the age of 65 years old among the subjects who were reviewed for cognitive function. The findings revealed that the beta-carotene supplementation tended to benefit people with the lowest dietary intake of carotenoids compared to normal women with adequate intake. The study also revealed no slowing down of cognitive function in women with preexisting comorbidities such as CVD; however, possible late effects were noticed (3).
Additionally, Rutjes et al. (2018) confirmed the earlier studies on the effect of vitamin supplementation and beta-carotene on the preservation of cognitive function in either young and old patients. The study was conducted to evaluate various trials conducted on participants 40 years older, to determine whether they can maintain their mental abilities and potentially reduce their risk of dementia while taking such respective supplements. Given that minerals and vitamins have many functions both in the body and brain, about 14 trials were subsequently reviewed, with eight trials involving antioxidants vitamins, including beta carotene, vitamin C, and vitamin E. A review of the studies observed that long-term supplementation with antioxidants and vitamins, especially beta-carotene, had some level of effect on cognitive function (6).
Beta-Carotene Might have Antioxidant Properties:
Several studies have shown beta-carotene to exhibit strong antioxidant capacity. A study by Khalid et al. (2014) presented the health benefits of beta-carotene, further explaining the potentially associated antioxidant features. The article conveyed that beta-carotene tends to have lasting protection on cellular damage. According to Khalid et al. (2014), a potent antioxidant capable of quenching 1000 free radicals tends to damage different types of cells in our body. This compound is considered potent at managing oxidative stress; hence it is linked to reducing heart disease and some forms of cancer. Such adaptive and protective qualities are linked with a reduction in the aging process and enhancement of the immune system (5).
Tilman Grune (2010) explored different benefits of beta-carotene as a significant source of vitamin A. The antioxidant activities were explored with a focus on both structural and experimental data. It was reviewed that beta-carotene shows some singlet oxygen quenching ability. This is found to help prevent photooxidative damage, which is usually facilitated by the singlet oxygen generation. The symptoms of the excessive singlet oxygen generation exposure to specific tissues were found to be improved by supplementation with high dose beta-carotene. The process was also found to help reduce sunburn or UV induced erythema, which is a result of prolonged skin exposure to ultraviolet rays (9).
Another important study was conducted to review the roles of antioxidant vitamins and beta-carotenoids on various aspects of degenerative diseases induced by or exacerbated by oxidative stress. The supplementation with beta-carotene is found to deactivate oxygen radicals. The antioxidant properties of beta-carotene have been linked with reducing issues associated with elevated levels of reactive oxygen species. The biological processes such as carcinogenesis, radiation damage, photobiological effects, and aging were linked with the beta-carotene (2).
Beta-Carotene Might Support a Healthy Heart:
Sesso et al. (2004) conducted a study that reviewed the role of plasma lycopene, carotenoids, and retinol on women’s risk of cardiovascular disease. It was found that the presence of a high concentration of lycopene and carotenoids causes some level of risk reduction in women with CVD. This was a prospective study conducted on 39,876 women who were initially free from CVD. Four hundred eighty-three women with CVD were compared with 483 control subjects. Age, smoking status, and follow up time was evaluated while their plasma lycopene, carotenoids, retinol, and cholesterol levels were measured. It was noted from this study that there was about a 50% reduction of cardiovascular disease risk (7).
Tavani & La Vecchia (1999) explored beta-carotene’s role in the risk reduction of coronary heart disease. This particular study was a review of observational and interventional studies. From the assessed research, six cohort studies reported findings on the relative risk of CHD and the role of beta-carotene with respect to participants exhibiting CHD. The findings showed some level of discrepancy between the two types of studies, observational vs. interventional. It was shown that the beneficial findings deduced from the observational studies are attributed to the consumption of foods rich in beta-carotene vs. supplementation with beta carotene supplements. A time-related factor was also considered to be an important factor in the observed outcomes. More extended periods of supplementation proved to be increasingly beneficial, helping to establish that a balanced diet rich in beta-carotene can aid in reducing the risk in individuals with CHD (8).
Lastly, Valtuena et al. (2007) conducted a study on the total dietary antioxidant capacity available to contribute to beta-carotene plasma concentrations and how it affects cardiovascular disease risk. This was a cross-sectional study conducted on 247 healthy individuals (140 men and 107 women). A 3-day food record, as well as varying factors, were recorded throughout the trial. The study, which explored the dietary characteristics and plasma levels of the tested vitamins and beta-carotene, showed that the total dietary antioxidant capacity is not a predictor of the plasma beta-carotene levels, especially in those who regularly consume alcohol. Additionally, it was found that alcohol negatively affects beta-carotene capacity levels, thereby decreasing the effectiveness of any of the benefits that beta-carotene has on reducing cardiovascular disease risk (10).
Carrots are packed with beta-carotene. Individuals who tend to be allergic to raw carrots can present with mild to severe reactions. Common symptoms to carrots may include: itchy tongue, mouth, lips, ears, or throat, swelling in the throat. More severe symptoms may include hives, breathing problems, coughing, sore throat, swollen skin, runny nose, and congestion. If you suspect you may have allergies to carrots, it is recommended that you speak with your healthcare provider before consuming beta-carotene or other associated fruits or vegetables that may contain beta-carotene.
According to historical studies, beta-carotene has been supplemented to up to 180 mg to treat a patient with erythropoietic protoporphyria without noted toxicity. Aside from this, it has also been seen that excess consumption of foods rich in beta-carotene has been linked with Hypercarotenemia or the development of yellow palms and/or soles. 3-6 mg of beta-carotene is considered a safe daily dosage for children, while 6-15 mg is considered appropriate for teenagers and adults.
It is important to note major side effects that could be associated with beta-carotene supplementation due to either allergic reactions or overconsumption. The common ones are the development of yellow palms, hands, and soles of feet referred to as carotenemia. Sometimes this discoloration may also develop on the face. Rare side effects associated with beta-carotene consumption may include diarrhea, dizziness, joint pain, or unusual bleeding. Canthaxanthin retinopathy is another side effect of too much beta carotene. It is characterized by yellow-golden specks in the eye, which are sometimes associated with visual field defects or problems with clarity. Lycopenodermia also results in discolored deep orange color on the skin temporarily.
Beta-carotene may decrease the effectiveness of some statin drugs and niacin (12).
- Grodstein F, et al. A randomized trial of beta carotene supplementation and cognitive function in men: the Physicians’ Health Study II. Arch Intern Med. 2007:12;167(20):2184-90. doi: 10.1001/archinte.167.20.2184.
- Helmut S, Stahl W. Vitamins E and C, a-carotene, and other carotenoids as antioxidant. Am J Clin Nutr. 1995;62:1315S-1321S. doi: 10.1093/ajcn/62.6.1315S.
- Kang JH, et al. Vitamin E, vitamin C and β-carotene and cognitive function among women with or at risk of cardiovascular disease: the WACS study. Circulation. 2009 119(21): 2772–2780. doi: 10.1161/CIRCULATIONAHA.108.816900
- Kim J K. An update on the potential health benefits of carotenes. EXCLI J. 2016; 15: 1–4. doi: 10.17179/excli2015-664
- Gul K, et al. Chemistry, encapsulation, and health benefits of β-carotene – A review. Cogent Food and Agriculture. 2015; 1:1.
- Rutjes A WS, et al. Vitamin and mineral supplementation for preventing cognitive deterioration in cognitively healthy people in mid and late-life. Cochrane Database Syst Rev. 2018(12): CD011906. doi: 10.1002/14651858.CD011906.pub2
- Sesso HD, et al. Plasma lycopene, other carotenoids, and retinol and the risk of cardiovascular disease in women. Am J Clin Nutr. 2004;79(1):47-53. doi: 10.1093/ajcn/79.1.47.
- Tavani A, La Vecchia C. Beta-carotene and risk of coronary heart disease. A review of observational and intervention studies. Biomed Pharmacother. 1999 Oct;53(9):409-16. doi: 10.1016/S0753-3322(99)80120-6.
- Grune T, et al. β-Carotene Is an Important Vitamin A Source for Humans. The Journal of Nutrition. 2010; 140(12): 2268S–2285S. doi: 10.3945/jn.109.119024
- Valtuena S, et al. The total antioxidant capacity of the diet is an independent predictor of plasma beta-carotene. Eur J Clin Nutr. 2007 Jan;61(1):69-76. doi: 10.1038/sj.ejcn.1602485.
- Evens M. History. http://www.chm.bris.ac.uk/motm/carotene/beta-carotene_history.html. Accessed 1 Jan 2020.
- Beta-carotene. https://www.webmd.com/vitamins/ai/ingredientmono-999/beta-carotene. Accessed 1 Jan 2020.