Pediatrics-2012-Forman-e1406-15.pdf

12 Pages
157 Views
Unlock Document

Department
Social Science
Course
SOSC 1009
Professor
George Georgopoulos
Semester
Winter

Description
    Organic Foods: Health and Environmental Advantages and Disadvantages Joel Forman, Janet Silverstein, COMMITTEE ON NUTRITION and COUNCIL ON ENVIRONMENTAL HEALTH Pediatrics 2012;130;e1406; originally published online October 22, 2012; DOI: 10.1542/peds.2012-2579   The online version of this article, along with updated information and s ervices, is located on the World Wide Web at: http://pediatrics.aappublications.org/content/130/5/e1406.full.html   PEDIATRICS is the official journal of the American Academy of Pediatrics . A monthly publication, it has been published continuously since 1948. PEDIATRICS i s owned, published, and trademarked by the American Academy of Pediatrics, 141 No rthwest Point Boulevard, Elk Grove Village, Illinois, 60007. Copyright © 2012 by th e American Academy of Pediatrics. All rights reserved. Print ISSN: 0031-4005. Online ISSN: 1098-4275. Downloaded from pediatrics.aappublications.org at York University Libraries on April 7, 2013 Guidance for the Clinician in Rendering Pediatric Care CLINICAL REPORT Organic Foods: Health and Environmental Advantages and Disadvantages Joel Forman, MD, Janet Silverstein, MD, COMMITTEE ON abstract NUTRITION, and COUNCIL ON ENVIRONMENTAL HEALTH The US market for organic foods has grown from $3.5 billion in 1996 to KEY WORDS organic food, produce, meat, dairy, growth hormone, antibiotic, $28.6 billion in 2010, according to the Organic Trade Association. Or- farming, diet ganic products are now sold in specialty stores and conventional supermarkets. Organic products contain numerous marketing claims ABBREVIATIONS GH—growth hormone and terms, only some of which are standardized and regulated. NOP—National Organic Program In terms of health advantages, organic diets have been convincingly USDA—US Department of Agriculture This document is copyrighted and is property of the American demonstrated to expose consumers to fewer pesticides associated Academy of Pediatrics and its Board of Directors. All authors with human disease. Organic farming has been demonstrated to have have filed conflict of interest statements with the American less environmental impact than conventional approaches. However, Academy of Pediatrics. Any conflicts have been resolved through current evidence does not support any meaningful nutritional benefits a process approved by the Board of Directors. The American or deficits from eating organic compared with conventionally grown Academy of Pediatrics has neither solicited nor accepted any commercial involvement in the development of the content of foods, and there are no well-powered human studies that directly dem- this publication. onstrate health benefits or disease protection as a result of consuming The guidance in this report does not indicate an exclusive course of treatment or serve as a standard of medical care. anorganic diet. Studies also have notdemonstrated any detrimentalor Variations, taking into account individual circumstances, may be disease-promotingeffectsfromanorganicdiet.Althoughorganicfoods appropriate. regularly command a significant price premium, well-designed farm- ing studies demonstrate that costs can be competitive and yields com- parable to those of conventional farming techniques. Pediatricians should incorporate this evidence when discussing the health and en- vironmental impact of organic foods and organic farming while con- tinuing to encourage all patients and their families to attain optimal nutritionand dietary variety consistent with the US Department of Agri- culture’s MyPlate recommendations. This clinical report reviews the health and environmental issues re- lated to organic food production and consumption. It defines the term www.pediatrics.org/cgi/doi/10.1542/peds.2012-2579 “organic,” reviews organic food-labeling standards, describes organic doi:10.1542/peds.2012-2579 and conventional farming practices, and explores the cost and envi- All clinical reports from the American Academy of Pediatrics ronmental implications of organic production techniques. It examines automatically expire 5 years after publication unless reaffirmed, the evidence available on nutritional quality and production contam- revised, or retired at or before that time. inants in conventionally produced and organic foods. Finally, this re- PEDIATRICS (ISSN Numbers: Print, 0031-4005; Online, 1098-4275). port provides guidance for pediatricians to assist them in advising Copyright © 2012 by the American Academy of Pediatrics their patients regarding organic and conventionally produced food choices. Pediatrics 2012;130:e1406–e1415 e1406 FROM THE AMERICAN ACADEMY OF PEDIATRICS Downloaded from pediatrics.aappublications.org at York University Libraries on April 7, 2013 FROM THE AMERICAN ACADEMY OF PEDIATRICS DEFINITION AND REGULATION OF Labeling ingredients or food groups on the ORGANIC FOODS principal display panel. For example, Consumers are confronted with a Definition wide range of food product marketing soup made with at least 70% organic terms, some regulated and some not ingredients and only organic vegetables Organic farming uses an approach to may be labeled either“soup made with growing crops and raising livestock that (Table 1). The labeling requirements of the NOP apply to raw, fresh products organic peas, potatoes, and carrot”sor avoids synthetic chemicals, hormones, “soup made with organic vegetables ”. antibiotic agents, genetic engineering, and processed products that contain organic agricultural ingredients. These and irradiation. In the United States, the Related Terms USDepartmentofAgriculture(USDA)has labeling requirements are based on the percentage of organic ingredients The NOP places no restrictions on the implemented the National Organic Pro- in a product. Products labeled “100% use of truthful labeling claims, such as gram (NOP) in response to the Organic Foods Production Act of 1990.The NOP organic” must contain only organically “no drugs or growth hormones used,” produced ingredients and processing “free range,” or “sustainably har- set labeling standards that have been in 3 effect since October 2002. NOP stand- aids (excluding water and salt). Prod- vested.” The USDA regulates the term ucts labeled “organic” must consist of “free range” for poultry products; to ards for organic food production in- clude many specfi ic requirements for at least 95% organically processed use this term, producers must dem- ingredients (excluding water and salt); onstrate that the poultry has been both crops and livestock. To qualify as the remaining 5% of ingredients may allowed “access to the outside.” 4 organic, crops must be produced on be conventional or synthetic but must According to Consumers Union’s eval- farms that have not used most synthetic be on the USDA’s approved list. Pro- uation, this means that a poultry pesticides, herbicides, and fertilizer for 3 years before harvest and have a su fif- cessed products that contain at least product comes from a bird that had at 70% organic ingredients can use the least 5 minutes of access to the out- cient buffer zone to decrease contami- doors each day. 4,5No standard defi- nation from adjacent lands. Genetic phrase“made with organic ingredient” s and list up to 3 of the organic nition exists for all other products engineering, ionizing radiation, and sewage sludge is prohibited. Soil fertil- TABLE 1 Commonly Used Food Product Marketing Terms Term Definition ity and nutrient content is managed primarily with cultivation practices, 100% organic Must contain only organically produced ingredients and crop rotations, and cover crops sup- processing aids (excluding water and salt). Organic Must consist of at least 95% organically produced ingredients plemented with animal and crop waste (excluding water and salt). Any remaining product zt,dsi ingredients must consist of nonagricultural substances approved on the National List. are managed primarily by physical, mechanical, and biological controls in- Made with organic ingredients Must contain at least 70% organic ingredients. Natural A product containing no artificial ingredient or added color and stead of with synthetic pesticides and that is only minimally processed (a process that does not herbicides. Excepto ins are allowed if fundamentally alter the raw product). The label must explain substances are on a national approved the use of the term. Free range Producers must demonstrate to the USDA that the poultry has list. Organic livestock must be reared been allowed access to the outside. without the routine use of antibiotic No hormones (pork or poultry) Hormones are not allowed in raising hogs or poultry. Therefore, the claim “no hormones added” cannot be used on the labels agents or growth hormones (GHs) and of pork or poultry unless it is followed by a statement that must be provided with access to the says “Federal regulations prohibit the use of hormones.” outdoors. If an animal is treated for No hormones (beef) The term “no hormones administered” may be approved for disease with antibiotic agents, it cannot use on the label of beef products if sufficient documentation be sold as organic. Preventive health is provided to the USDA by the producer showing no hormones have been used in raising the animals. practices include vaccination and vita- No antibiotics (red meat and poultrThe terms “no antibiotics added” may be used on labels for min and mineral supplementation. The meat or poultry products if sufficient documentation is provided by the producer to the USDA demonstrating that USDA certifies organic products accord- the animals were raised without antibiotics. ing to these guidelines. Organic farmers Certified “Certified” implies that the USDA’s Food Safety and Inspection Service and the Agriculture Marketing Service have officially must apply for certification, pass a evaluated a meat product. test, and pay a fee. The NOP requires annual inspections to ensure ongoing Chemical free This term is not allowed to be used on a label. There are no restrictions on use of other truthful labeling claims, such as “no drugs or growth hormones used,” or compliance with these standards. “sustainably harvested.” PEDIATRICS Volume Downloaded from pediatrics.aappublications.org at York University Libraries on April 7, 2013 e1407 carrying the “free range” label, such increased propensity to purchase or- number of nutrients reported in vari- as beef, pork, or eggs; the use of the ganic food is the level of consumer ous articles, the authors grouped the term, however, is allowed. education.14–21Organic products, how- nutrients into large categories. They ever, cost up to 40% more. found no significant differences in The term “natural” or “all natural” is defined by the USDA for meat and most nutrients, with the exception of poultry and means that the products NUTRITIONAL QUALITY OF ORGANIC higher nitrogen content in conven- tional produce and higher titratable contain no artificial flavoring, color VERSUS CONVENTIONAL FOOD ingredients, chemical preservatives, Produce acidity and phosphorus in organic or artificial or synthetic ingredients produce.29 Better-quality research that Consumers believe that organic pro- accounts for the many confounding and are “minimally processed.” Mini- duce is more nutritious than conven- mally processed means that the raw variables is needed to elucidate po- product was not fundamentally al- tionally grown produce, but the tential differences in nutrients and the research to support that belief is not clinical importance of nutrients that tered. Additional USDA definitions of definitive. Many studies have demon- other labeling terms can be found in may be different. At this time, however, publicly available USDA fact sheets.4 strated no important differences in there does not appear to be convincing carbohydrate or vitamin and mineral evidence of a substantial difference in The term “raw” milk refers to un- content.22 Some studies have found pasteurized milk. All milk certified as nutritional quality of organic versus lower nitrate content in organic foods conventional produce. organic by the USDA is pasteurized. versus conventionally grown foods, Raw milk can contain harmful bacteria, which is potentially desirable because Milk such as Salmonella species, Escher- of the association of nitrates with in- The composition of dairy products, ichia coli O157:H7, Listeria species, creased risk of gastrointestinal cancer including milk, is affected by many Campylobacter species, and Brucella species, and has been repeatedly as- and, in infants, methemoglobinemia. factors, including differences caused Higher vitamin C concentrations were by genetic variability and cattle breed; sociated with outbreaks of disease found in organic leafy vegetables, thus, the results of studies assessing caused by these pathogens. The Amer- ican Academy of Pediatrics, US Food such as spinach, lettuce, and chard milk composition must be interpreted versus the same conventionally pro- with caution. In general, milk has the and Drug Administration, and Centers duced vegetables in 21 of 36 (58%) same protein, vitamin, trace mineral for Disease Control and Prevention 22 advise consumers not to consume raw studies. Other studies have found content, and lipids from both organi- higher total phenols in organic pro- cally and conventionally reared cows. milk.6–8 duce versus conventionally grown Fat-soluble antioxidants and vitamins produce and have postulated health present in milk come primarily from SCOPE OF CONSUMER USE, benefits from antioxidant effects.23 the natural components of the diet or PRICES, AND TRENDS IN ORGANIC from the synthetic compounds used to FOOD Several attempts have been made to review the relevant literature and supplement the feed ingested by lac- In 2008, more than two-thirds of US draw conclusions on organic versus tating cows.30 consumers bought some organic prod- conventional foods, but the results are One recent study examined antibiotic ucts, and more than one-quarter bought conflicting.24–28A large systematic re- and microorganism content, hormone organic at least weekly. The amount of view published in 2009 found that concentrations, and nutritional values US acreage dedicated to organic crops fewer than 20% of 292 articles with of milk in 334 samples from 48 states has doubled since 1997. 9 Consumers potentially relevant titles met criteria labeled as organic, not treated with choose organic food in the belief that for quality, leaving only 55 studies to bovine GH (referred to as“GH-free”), or organic foods are more nutritious, have assess. The authors highlighted the conventional. This study found that milk fewer additives and contaminants, and fact that the nutrient content of pro- labeled “conventional” had lower bac- are grown more sustainably. 10 Some duce is affected by numerous factors, terial counts than milk that was or- 11,12 studies suggest that families with including the geographic location of ganic or GH-free, although this was not children and adolescents or younger the farm, local soil characteristics, clinically significant. Estradiol and pro- consumers in general are more likely climactic conditions that can vary by gesterone concentrations were lower in to buy organic fruits and vegetables season, maturity at time of harvest, conventional milk than in organic milk, than are other consumers. 13The factor and storage and time to testing but GH-free milk had progesterone most consistently associated with the after harvest. Because of the large concentrations similar to conventional e1408 FROM THE AMERICAN ACADEMY OF PEDIATRICS Downloaded from pediatrics.aappublications.org at York University Libraries on April 7, 2013 FROM THE AMERICAN ACADEMY OF PEDIATRICS milk and estradiol concentrations sim- stomach environment, it must be given 1970s and 1980s using radioimmuno- ilar to organic milk. Macronutrient by injection. GH is species-specific, and assay methods. One study demon- composition was similar, although or- bovine GH is biologically inactive in strated concentrations of estrogens ganic milk had 0.1% more protein than humans. Because of this, any bovine found in meat residues were low and 31 the other 2 milk types. GH in food products has no physiologic overlapped with concentrations found Several studies have demonstrated effect on humans, even if it were in untreated cows. 34 Gas chromatog- that organic milk has higher concen- absorbed intact from the gastroin- raphy measurements of sex steroids trations of antioxidants and poly- testinal tract. In addition, 90% of bo- progesterone, testosterone, 17β es- unsaturated fatty acids. However, it is vine GH in milk is destroyed during the tradiol, and estrone and their metab- important to recognize that the com- pasteurization process. There is no olites in meat products, fish, poultry, evidence that the gross composition of position of milk is strongly related to milk, and eggs revealed insignificant what the cows eat. This differs by time milk (fat, protein, and lactose) is al- amounts compared with daily pro- of year (outdoors in the summer, in- tered by treatment with bovine GH, nor duction of these steroids in adults and is there any evidence that the vitamin 35 doorforage inthewinter)andwhether children. Furthermore, 98% to 99% the farms are high or low input. High- and mineral contents of milk are of endogenous sex steroids are bound input farms supplement the diets of changed by GH treatment. 31 by sex-hormone-binding globulin, ren- cattle with proprietary minerals and GHtreatmentofcowsmayactuallyhave dering them metabolically inactive as vitamins. Low-input farms use meth- environmental benefits. GH increases only the unbound (free) forms of sex ods similar to those used in organic milk production per cow, which could steroids are metabolically active. Syn- farming but do not follow all the theoretically decrease the number of thetic sex steroids (zeranol, melen- restrictions prescribed by organic cows needed to produce a given gestrol, and trenbolone) commonly farming standards; they use mineral amountofmilk,with resultantneedfor used in animals have lower affinities fertilizers but at lowerlevels than used fewer cows and, thus, less cultivated to sex-hormone-binding globulin and, by conventional high-input systems. land needed to feed the cows. In ad- therefore, are potentially more meta- One study comparing milk from all 3 dition, fewer cows would result in the bolically active unbound sex steroids. production systems found milk from production of less manure with re- These hormones do not occur naturally boththelow-inputorganicandlow-input sultant reduced methane production in humans, and although the concen- nonorganic systems generally had sig- and less carbon dioxide production, trations of these hormones are low in nificantly higher concentrations of nu- with a resultant salutary effect on cattle, the biological effects in humans, tritionally desirable unsaturated fatty global warming. 33 if any, are unknown. acids (conjugated linoleic acid and Ingestion of milk from estrogen-treated omega-3 fatty acids) and fat-soluble Sex Steroids cows appears to be safe for children. antioxidants compared with milk from Estradiol and estrone concentrations in the high-input systems; milk derived Treatment of cattle with sex steroids increases lean muscle mass, accel- organic and conventional 1%, 2%, and fromcowsinbothorganiccertifiedand wholemilkwerethesame,althoughthe nonorganic low-input systems was erates the rate of growth, and is an concentrations of sex steroids were significantly higher in conjugated lino- efficient way to increase meat yield. Estrogens are usually given by im- higher as the fat content of the milk leic acid content than was milk from increased and were lower than en- conventional high-input systems.32 plantation of estrogen pellets into the dogenous production rates in humans. skin on the underside of the ear, and the ear is discarded during slaughter. Estradiol concentrations in milk ranged HORMONES from 0.4 to 1.1 pg/mL, and estrone GH Unlike GH, sex steroids arenotspecies- concentrations ranged from 2.9 to 7.9 specific and may be given orally Hormone supplementation of farm without degradation in the stomach. In pg/mL, with the lowest concentrations animals, especially with GH, is one of 1998, the Food and Agriculture Orga- in skim milk and the highest in whole milk.36 the major reasons consumers state nization of the United Nations and they prefer to buy organic foods. Bo- World Health Organization jointly con- Endogenous estradiol concentrations vine GH (ie, recombinant bovine so- cluded that meat from estradiol-trea- are as high as 80 pg/mL in 2- to 4- matotropin) increases milk yield by ted animals was safe on the basis of month-oldfemaleinfantsand40pg/mL 10% to 15% and is lipotropic in cows. data obtained from residue levels in in 2- to 4-month-old male infants. Hu- Because GH is degraded in the acidic meat from studies performed in the man milk has estradiol concentrations PEDIATRICS Volume 130, Number 5, November 2012 e1409 Downloaded from pediatrics.aappublications.org at York University Libraries on April 7, 2013 as high as 39 pg/mL and estrone that higher red meat consumption in used in risk assessments are highly (which has approximately half the adolescence may increase breast overestimated and should be reeval- potency of estradiol) concentrations cancer risk, tracked cases of cancer uated by using current assays. 41It is as high as 1177 pg/mL. Human co- prospectively after the dietary history therefore important to determine the lostrum has even higher estrogen was obtained, it was limited by relative importance of hormone treat- concentrations of 500 pg/mL and 4000 a number of factors, including the ment of animals in the context of other to 5000 pg/mL for estradiol and es- dependence on subjects’ long-term environmental endocrine disrupters trone, respectively. Cow milk, by memory of amount of food eaten through long-term longitudinal studies comparison, has estradiol concen- decades previously, the likelihood that in children. trations of 4 to 14 pg/mL and estrone hormone concentrations in meat were 37,38 concentrations of 34 to 55 pg/mL. higher in that period, and the lack NONTHERAPEUTIC USE OF It has been postulated that ingested of direct measurement of hormonal ANTIBIOTIC AGENTS exposure. 40 Longitudinal prospective estrogen in food derived from sex- Conventional animal husbandry fre- hormone-treated animals may play studies are needed to compare the quently includes the administration of aroleinearlierdevelopmentofpuberty risk of breast cancer in women who antibiotic agents in nontherapeutic eat meat from hormone-treated ani- and increasing risk of breast cancer. doses to livestock to promote growth However, no studies have supported mals with the risk in women who eat and increase yields. Between 40% and this hypothesis in humans. Studies in meat from untreated animals. 80% of the antimicrobial agents used in animals demonstrating carcinogenic Endocrine disrupters, chemicals that the United States each year are used in and teratogenic effects of estrogens interfere with hormone signaling sys- food animals, three-quarters of which usedhighdosesofestradiolandcannot tems,arepervasive inourenvironment. isnontherapeutic.Manyofthese agents be extrapolated to the low doses of Among the most commonly found en- areidenticalorsimilar todrugsusedin sex steroids found in the food supply. docrine disrupters are bisphenol A, humans. 42Evidence is clear that such Estrogen concentrations in the myo- found in industrial chemicals and nontherapeutic use promotes the de- metrium, breast, and vagina of post- plastics; phthalates, found in personal velopment of drug-resistant organisms menopausal women, although still low, care items such as cosmetics; and in the animals and that these organ- are higher than those found in serum, isms then colonize the intestines of lavenderand tea tree oil, found in many and additional studies are needed to hair products, soaps, and lotions; all people living on farms where this determine the significance of these have estrogenic properties. Endocrine practice occurs. 43 Evidence is also low concentrations of sex steroids in ample that human disease caused by 39 disrupters are postulated to be in- estrogen-sensitive tissues. volved in the increased occurrence of antibiotic-resistant organisms spread An association has been found be- genital abnormalities among newborn through the food chain. 44 Because or- ganic farming prohibits the non- tween red meat consumption in high boys and precocious puberty in girls. school girls and the development of Recent literature on sex steroid con- therapeutic use of antibiotic agents, it breast cancer later in life. A 7-year centrations and their physiologic roles could contribute to a reduction in the threat of human disease caused by prospective longitudinal study of 39268 during childhood indicate that con- premenopausal women 33 to 53 years centrations of estradiol in prepubertal drug-resistant organisms. of age who filled out a comprehensive children are lower than originally SYNTHETIC CHEMICAL EXPOSURE diet history of foods eaten while in high thoughtandthatchildrenareextremely school in the 1960s and 1970s revealed sensitive to estradiol and may respond Pesticides a linear association between each ad- with increased growth and/or breast Pesticides have a host of toxic effects ditional 100 g of red meat consumed in development even at serum concen- that range from acute poisonings to high school per day with the risk of trations below the current detection subtle subclinical effects from long- developing hormone-receptor-positive limits.1 No threshold has been estab- term, low-dose exposure. 45 Organo- premenopausal tumors (relative risk, lished below which there are no hor- phosphate pesticides are commonly 1.36; 95% confidence interval, 1.08– monal effects on exposed children. used in agriculture, and poisoning is 1.70; P = .008). Red meat ingestion did Furthermore, the daily endogenous a persistent problem in the agricul- not increase the risk of hormone- production rates of sex steroids in tural setting. From 1998 to 2005, 3271 receptor-negative tumors. Although children estimated by the Food and cases of agricultural occupational this intriguing study, which suggested Drug Administration in 1999 and still acute pesticide poisoning were e1410 FROM THE AMERICAN ACADEMY OF PEDIATRICS Downloaded from pediatrics.aappublications.org at York University Libraries on April 7, 2013 FROM THE AMERICAN ACADEMY OF PEDIATRICS reported to the California Department consumed conventional produce demon- cross-sectional studies. These studies of Pesticide Regulation and the Na- strated that urinary pesticide residues are limited by a number of factors, tional Institute of Occupational Health’s were reduced to almost nondetectable including difficulties measuring past SENSOR-Pesticides program. This con- levels (below 0.3 μg/L for malathion exposures and the lack of a positive stitutes a rate of 56 cases per 100000 dicarboxylic acid, for example) when temporal relationship between expo- full-time equivalents, 38 times the rate they were changed to an organic sure and outcome. It is difficult to di- produce diet for 5 days. In addition, rectly extrapolate from these studies observed in nonagricultural occupa- tions.6 Chronic exposure among farm residues varied with seasonal intake and draw conclusions about potential workers has been associated with nu- of produce, suggesting that dietary toxicity at the levels of pesticide ex- intake of organophosphate pesticides posure documented from dietary in- merous adult health problems, in- cluding respiratory problems, memory represented the major source of ex- take of conventional produce. Data disorders, dermatologic conditions, de- posure in these young children. 59 derived from large prospective cohort studies may address some of these pression, neurologic de ficits including Although a common practice, rinsing Parkinson disease, miscarriages, birth conventionallyfarmedproducereduces shortcomings. defects, and cancer. 47–50Prenatal or- some but not all pesticide residues on ganophosphate pesticide exposure has produce to varying degrees but has ENVIRONMENTAL IMPACT AND been associated with adverse birth not been proven to decrease human PRODUCTION EFFICIENCY OF outcomes, such as decreased birth 60 ORGANIC VERSUS CONVENTIONAL exposure. weight and length 51 and smaller head Pesticide metabolite concentrations FARMING METHODS circumference.52 A large prospective observed in studies that examined ex- Environmental Impact birth cohort study that measured pes- posure in farming communities as well A major subject in the organic debate ticide exposure in pregnant farm as in residential settings were in the workers in California and followed their is whether organic farming methods same range as those observed in sub- have less impact on the environment, offspring found lower mental de- jects consuming conventional produce velopment index scores at 24 months of in studies of biological exposure can be equally as productive, and can age53 and attentional problems at 3.5 be no more expensive than conven- 54 measures for organic versus conven- ti
More Less

Related notes for SOSC 1009

Log In


OR

Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


OR

By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.


Submit