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In medieval Poland , mead had a status equivalent to that of imported luxuries, such as spices and wines. During Lent, kings and schoolboys, commoners and nobility, all complained about being deprived of meat for the long, hard weeks of solemn contemplation of their sins. The Roman Catholic , Eastern Orthodox Churches and their calendars had great influence on eating habits; consumption of meat was forbidden for a full third of the year for most Christians. It was also of vital importance that food of differing properties not be mixed. Zoe Lau - November 1, These blogs are my favorite blogs and inspirations!

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It would mostly come from cows, but milk from goats and sheep was also common. Plain fresh milk was not consumed by adults except the poor or sick, and was usually reserved for the very young or elderly. Poor adults would sometimes drink buttermilk or whey or milk that was soured or watered down. On occasion it was used in upper-class kitchens in stews, but it was difficult to keep fresh in bulk and almond milk was generally used in its stead.

Cheese was far more important as a foodstuff, especially for common people, and it has been suggested that it was, during many periods, the chief supplier of animal protein among the lower classes. There were also whey cheeses , like ricotta , made from by-products of the production of harder cheeses. Cheese was used in cooking for pies and soups, the latter being common fare in German-speaking areas.

Butter , another important dairy product, was in popular use in the regions of Northern Europe that specialized in cattle production in the latter half of the Middle Ages, the Low Countries and Southern Scandinavia.

While most other regions used oil or lard as cooking fats, butter was the dominant cooking medium in these areas. Its production also allowed for a lucrative butter export from the 12th century onward. While all forms of wild game were popular among those who could obtain it, most meat came from domestic animals. Domestic working animals that were no longer able to work were slaughtered but not particularly appetizing and therefore were less valued as meat.

Beef was not as common as today because raising cattle was labor-intensive, requiring pastures and feed, and oxen and cows were much more valuable as draught animals and for producing milk. Mutton and lamb were fairly common, especially in areas with a sizeable wool industry, as was veal. Domestic pigs often ran freely even in towns and could be fed on just about any organic waste, and suckling pig was a sought-after delicacy.

Just about every part of the pig was eaten, including ears, snout, tail, tongue , and womb. Intestines, bladder and stomach could be used as casings for sausage or even illusion food such as giant eggs. Among the meats that today are rare or even considered inappropriate for human consumption are the hedgehog and porcupine , occasionally mentioned in late medieval recipe collections.

In England, they were deliberately introduced by the 13th century and their colonies were carefully protected. They were of particular value for monasteries, because newborn rabbits were allegedly declared fish or, at least, not-meat by the church and therefore they could be eaten during Lent.

A wide range of birds were eaten, including swans , peafowl , quail , partridge , storks , cranes , larks , linnets and other songbirds that could be trapped in nets, and just about any other wild bird that could be hunted. Swans and peafowl were domesticated to some extent, but were only eaten by the social elite, and more praised for their fine appearance as stunning entertainment dishes, entremets , than for their meat. As today, geese and ducks had been domesticated but were not as popular as the chicken , the fowl equivalent of the pig.

But at the Fourth Council of the Lateran , Pope Innocent III explicitly prohibited the eating of barnacle geese during Lent, arguing that they lived and fed like ducks and so were of the same nature as other birds.

Meats were more expensive than plant foods. Though rich in protein , the calorie -to-weight ratio of meat was less than that of plant food. Meat could be up to four times as expensive as bread. Fish was up to 16 times as costly, and was expensive even for coastal populations.

This meant that fasts could mean an especially meager diet for those who could not afford alternatives to meat and animal products like milk and eggs. It was only after the Black Death had eradicated up to half of the European population that meat became more common even for poorer people. The drastic reduction in many populated areas resulted in a labor shortage, meaning that wages dramatically increased. It also left vast areas of farmland untended, making them available for pasture and putting more meat on the market.

Although less prestigious than other animal meats, and often seen as merely an alternative to meat on fast days, seafood was the mainstay of many coastal populations.

Also included were the beaver , due to its scaly tail and considerable time spent in water, and barnacle geese , due to the belief that they developed underwater in the form of barnacles. The Holy Roman Emperor Frederick II examined barnacles and noted no evidence of any bird-like embryo in them, and the secretary of Leo of Rozmital wrote a very skeptical account of his reaction to being served barnacle goose at a fish-day dinner in Especially important was the fishing and trade in herring and cod in the Atlantic and the Baltic Sea.

The herring was of unprecedented significance to the economy of much of Northern Europe, and it was one of the most common commodities traded by the Hanseatic League , a powerful north German alliance of trading guilds. Kippers made from herring caught in the North Sea could be found in markets as far away as Constantinople.

Stockfish , cod that was split down the middle, fixed to a pole and dried, was very common, though preparation could be time-consuming, and meant beating the dried fish with a mallet before soaking it in water. A wide range of mollusks including oysters , mussels and scallops were eaten by coastal and river-dwelling populations, and freshwater crayfish were seen as a desirable alternative to meat during fish days.

Compared to meat, fish was much more expensive for inland populations, especially in Central Europe, and therefore not an option for most. Freshwater fish such as pike , carp , bream , perch , lamprey and trout were common. While in modern times, water is often drunk with a meal, in the Middle Ages, however, concerns over purity, medical recommendations and its low prestige value made it less favored, and alcoholic beverages were preferred.

They were seen as more nutritious and beneficial to digestion than water, with the invaluable bonus of being less prone to putrefaction due to the alcohol content. Wine was consumed on a daily basis in most of France and all over the Western Mediterranean wherever grapes were cultivated.

Further north it remained the preferred drink of the bourgeoisie and the nobility who could afford it, and far less common among peasants and workers.

The drink of commoners in the northern parts of the continent was primarily beer or ale. Juices , as well as wines, of a multitude of fruits and berries had been known at least since Roman antiquity and were still consumed in the Middle Ages: Medieval drinks that have survived to this day include prunellé from wild plums modern-day slivovitz , mulberry gin and blackberry wine.

Many variants of mead have been found in medieval recipes, with or without alcoholic content. However, the honey -based drink became less common as a table beverage towards the end of the period and was eventually relegated to medicinal use.

This is partially true since mead bore great symbolic value at important occasions. When agreeing on treaties and other important affairs of state, mead was often presented as a ceremonial gift.

It was also common at weddings and baptismal parties, though in limited quantity due to its high price. In medieval Poland , mead had a status equivalent to that of imported luxuries, such as spices and wines. Plain milk was not consumed by adults except the poor or sick, being reserved for the very young or elderly, and then usually as buttermilk or whey.

Fresh milk was overall less common than other dairy products because of the lack of technology to keep it from spoiling. However, neither of these non-alcoholic social drinks were consumed in Europe before the late 16th and early 17th century. Wine was commonly drunk and was also regarded as the most prestigious and healthy choice. According to Galen 's dietetics it was considered hot and dry but these qualities were moderated when wine was watered down.

Unlike water or beer, which were considered cold and moist, consumption of wine in moderation especially red wine was, among other things, believed to aid digestion, generate good blood and brighten the mood.

The first pressing was made into the finest and most expensive wines which were reserved for the upper classes. The second and third pressings were subsequently of lower quality and alcohol content. Common folk usually had to settle for a cheap white or rosé from a second or even third pressing, meaning that it could be consumed in quite generous amounts without leading to heavy intoxication.

For the poorest or the most pious , watered-down vinegar similar to Ancient Roman posca would often be the only available choice. The aging of high quality red wine required specialized knowledge as well as expensive storage and equipment, and resulted in an even more expensive end product. Judging from the advice given in many medieval documents on how to salvage wine that bore signs of going bad, preservation must have been a widespread problem.

Even if vinegar was a common ingredient, there was only so much of it that could be used. In the 14th century cookbook Le Viandier there are several methods for salvaging spoiling wine; making sure that the wine barrels are always topped up or adding a mixture of dried and boiled white grape seeds with the ash of dried and burnt lees of white wine were both effective bactericides , even if the chemical processes were not understood at the time.

Wine was believed to act as a kind of vaporizer and conduit of other foodstuffs to every part of the body, and the addition of fragrant and exotic spices would make it even more wholesome. Spiced wines were usually made by mixing an ordinary red wine with an assortment of spices such as ginger , cardamom , pepper , grains of paradise , nutmeg , cloves and sugar.

These would be contained in small bags which were either steeped in wine or had liquid poured over them to produce hypocras and claré. By the 14th century, bagged spice mixes could be bought ready-made from spice merchants. While wine was the most common table beverage in much of Europe, this was not the case in the northern regions where grapes were not cultivated. Those who could afford it drank imported wine, but even for nobility in these areas it was common to drink beer or ale , particularly towards the end of the Middle Ages.

In England , the Low Countries , northern Germany , Poland and Scandinavia , beer was consumed on a daily basis by people of all social classes and age groups. For most medieval Europeans, it was a humble brew compared with common southern drinks and cooking ingredients, such as wine, lemons and olive oil. Even comparatively exotic products like camel 's milk and gazelle meat generally received more positive attention in medical texts. Beer was just an acceptable alternative and was assigned various negative qualities.

In , the Sienese physician Aldobrandino described beer in the following way:. But from whichever it is made, whether from oats, barley or wheat, it harms the head and the stomach, it causes bad breath and ruins the teeth , it fills the stomach with bad fumes, and as a result anyone who drinks it along with wine becomes drunk quickly; but it does have the property of facilitating urination and makes one's flesh white and smooth.

The intoxicating effect of beer was believed to last longer than that of wine, but it was also admitted that it did not create the "false thirst" associated with wine. Though less prominent than in the north, beer was consumed in northern France and the Italian mainland. Perhaps as a consequence of the Norman conquest and the travelling of nobles between France and England, one French variant described in the 14th century cookbook Le Menagier de Paris was called godale most likely a direct borrowing from the English "good ale" and was made from barley and spelt , but without hops.

In England there were also the variants poset ale , made from hot milk and cold ale, and brakot or braggot , a spiced ale prepared much like hypocras. That hops could be used for flavoring beer had been known at least since Carolingian times, but was adopted gradually due to difficulties in establishing the appropriate proportions. Before the widespread use of hops, gruit , a mix of various herbs , had been used. Gruit had the same preserving properties as hops, though less reliable depending on what herbs were in it, and the end result was much more variable.

Another flavoring method was to increase the alcohol content, but this was more expensive and lent the beer the undesired characteristic of being a quick and heavy intoxicant. Hops may have been widely used in England in the tenth century; they were grown in Austria by and in Finland by , and possibly much earlier. Before hops became popular as an ingredient, it was difficult to preserve this beverage for any time, and so, it was mostly consumed fresh.

Quantities of beer consumed by medieval residents of Europe, as recorded in contemporary literature, far exceed intakes in the modern world. For example, sailors in 16th century England and Denmark received a ration of 1 imperial gallon 4. Polish peasants consumed up to 3 litres 0.

In the Early Middle Ages beer was primarily brewed in monasteries , and on a smaller scale in individual households. By the High Middle Ages breweries in the fledgling medieval towns of northern Germany began to take over production. Though most of the breweries were small family businesses that employed at most eight to ten people, regular production allowed for investment in better equipment and increased experimentation with new recipes and brewing techniques.

These operations later spread to the Netherlands in the 14th century, then to Flanders and Brabant , and reached England by the 15th century.

Hopped beer became very popular in the last decades of the Late Middle Ages. When perfected as an ingredient, hops could make beer keep for six months or more, and facilitated extensive exports.

In turn, ale or beer was classified into "strong" and "small", the latter less intoxicating, regarded as a drink of temperate people, and suitable for consumption by children. As late as , John Locke stated that the only drink he considered suitable for children of all ages was small beer, while criticizing the apparently common practice among Englishmen of the time to give their children wine and strong alcohol.

By modern standards, the brewing process was relatively inefficient, but capable of producing quite strong alcohol when that was desired. One recent attempt to recreate medieval English "strong ale" using recipes and techniques of the era albeit with the use of modern yeast strains yielded a strongly alcoholic brew with original gravity of 1.

The ancient Greeks and Romans knew of the technique of distillation , but it was not practiced on a major scale in Europe until some time around the 12th century, when Arabic innovations in the field combined with water-cooled glass alembics were introduced.

Distillation was believed by medieval scholars to produce the essence of the liquid being purified, and the term aqua vitae "water of life" was used as a generic term for all kinds of distillates. Alcoholic distillates were also occasionally used to create dazzling, fire-breathing entremets a type of entertainment dish after a course by soaking a piece of cotton in spirits.

It would then be placed in the mouth of the stuffed, cooked and occasionally redressed animals, and lit just before presenting the creation. Aqua vitae in its alcoholic forms was highly praised by medieval physicians. In Arnaldus of Villanova wrote that "[i]t prolongs good health, dissipates superfluous humours, reanimates the heart and maintains youth.

By the 13th century, Hausbrand literally "home-burnt" from gebrannter wein, brandwein ; "burnt [distilled] wine" was commonplace, marking the origin of brandy. Towards the end of the Late Middle Ages, the consumption of spirits became so ingrained even among the general population that restrictions on sales and production began to appear in the late 15th century. In the city of Nuremberg issued restrictions on the selling of aquavit on Sundays and official holidays.

Spices were among the most luxurious products available in the Middle Ages, the most common being black pepper , cinnamon and the cheaper alternative cassia , cumin , nutmeg , ginger and cloves. They all had to be imported from plantations in Asia and Africa , which made them extremely expensive, and gave them social cachet such that pepper for example was hoarded, traded and conspicuously donated in the manner of gold bullion.

The value of these goods was the equivalent of a yearly supply of grain for 1. Sugar , unlike today, was considered to be a type of spice due to its high cost and humoral qualities. Even when a dish was dominated by a single flavor it was usually combined with another to produce a compound taste, for example parsley and cloves or pepper and ginger.

Common herbs such as sage , mustard , and parsley were grown and used in cooking all over Europe, as were caraway , mint , dill and fennel. Many of these plants grew throughout all of Europe or were cultivated in gardens, and were a cheaper alternative to exotic spices. Mustard was particularly popular with meat products and was described by Hildegard of Bingen — as poor man's food. While locally grown herbs were less prestigious than spices, they were still used in upper-class food, but were then usually less prominent or included merely as coloring.

Anise was used to flavor fish and chicken dishes, and its seeds were served as sugar-coated comfits. Surviving medieval recipes frequently call for flavoring with a number of sour, tart liquids. Wine, verjuice the juice of unripe grapes or fruits vinegar and the juices of various fruits, especially those with tart flavors, were almost universal and a hallmark of late medieval cooking. In combination with sweeteners and spices, it produced a distinctive "pungeant, fruity" flavor.

Equally common, and used to complement the tanginess of these ingredients, were sweet almonds. They were used in a variety of ways: This last type of non-dairy milk product is probably the single most common ingredient in late medieval cooking and blended the aroma of spices and sour liquids with a mild taste and creamy texture. Salt was ubiquitous and indispensable in medieval cooking. Salting and drying was the most common form of food preservation and meant that fish and meat in particular were often heavily salted.

Many medieval recipes specifically warn against oversalting and there were recommendations for soaking certain products in water to get rid of excess salt. The richer the host, and the more prestigious the guest, the more elaborate would be the container in which it was served and the higher the quality and price of the salt.

Wealthy guests were seated " above the salt ", while others sat "below the salt", where salt cellars were made of pewter, precious metals or other fine materials, often intricately decorated. The rank of a diner also decided how finely ground and white the salt was.

Salt for cooking, preservation or for use by common people was coarser; sea salt, or "bay salt", in particular, had more impurities, and was described in colors ranging from black to green. Expensive salt, on the other hand, looked like the standard commercial salt common today. The term " dessert " comes from the Old French desservir , "to clear a table", literally "to un-serve", and originated during the Middle Ages. It would typically consist of dragées and mulled wine accompanied by aged cheese , and by the Late Middle Ages could also include fresh fruit covered in sugar, honey or syrup and boiled-down fruit pastes.

Sugar , from its first appearance in Europe, was viewed as much as a drug as a sweetener; its long-lived medieval reputation as an exotic luxury encouraged its appearance in elite contexts accompanying meats and other dishes that to modern taste are more naturally savoury. There was a wide variety of fritters , crêpes with sugar, sweet custards and darioles , almond milk and eggs in a pastry shell that could also include fruit and sometimes even bone marrow or fish.

Marzipan in many forms was well known in Italy and southern France by the s and is assumed to be of Arab origin. The English chefs also had a penchant for using flower petals such as roses , violets , and elder flowers.

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Furthermore, since ob gene expression was increased, not decreased, in human obesity, it suggested resistance to leptin to be a possibility. Subsequent studies in confirmed that the db gene encodes the leptin receptor , and that it is expressed in the hypothalamus , a region of the brain known to regulate the sensation of hunger and body weight. Coleman and Friedman have been awarded numerous prizes acknowledging their roles in discovery of leptin, including the Gairdner Foundation International Award , [27] the Shaw Prize , [28] the Lasker Award , [29] the BBVA Foundation Frontiers of Knowledge Award [30] and the King Faisal International Prize , [31] Leibel has not received the same level of recognition from the discovery because he was omitted as a co-author of a scientific paper published by Friedman that reported the discovery of the gene.

The discovery of leptin also is documented in a series of books including Fat: Fighting the Obesity Epidemic and Rethinking Thin: The New Science of Weight Loss and the Myths and Realities of Dieting review the work in the Friedman laboratory that led to the cloning of the ob gene, while The Hungry Gene draws attention to the contributions of Leibel. The Ob Lep gene Ob for obese, Lep for leptin is located on chromosome 7 in humans.

A human mutant leptin was first described in , [38] and subsequently six additional mutations were described. All of those affected were from Eastern countries; and all had variants of leptin not detected by the standard immunoreactive technique, so leptin levels were low or undetectable. The most recently described eighth mutation reported in January , in a child with Turkish parents, is unique in that it is detected by the standard immunoreactive technique, where leptin levels are elevated; but the leptin does not turn on the leptin receptor, hence the patient has functional leptin deficiency.

A nonsense mutation in the leptin gene that results in a stop codon and lack of leptin production was first observed in mice in In the mouse gene, arginine is encoded by CGA and only requires one nucleotide change to create the stop codon TGA. The corresponding amino acid in humans is encoded by the sequence CGG and would require two nucleotides to be changed to produce a stop codon, which is much less likely to happen.

A recessive frameshift mutation resulting in a reduction of leptin has been observed in two consanguineous children with juvenile obesity. A Human Genome Equivalent HuGE review in looked at studies of the connection between genetic mutations affecting leptin regulation and obesity. They reviewed a common polymorphism in the leptin gene A19G; frequency 0.

They found no association between any of the polymorphisms and obesity. Other rare polymorphisms have been found but their association with obesity are not consistent. A single case of a homozygous transversion mutation of the gene encoding for leptin was reported in January The transversion of c. The mutant leptin could neither bind to nor activate the leptin receptor in vitro , nor in leptin-deficient mice in vivo.

It was found in a two-year-old boy with extreme obesity with recurrent ear and pulmonary infections. Treatment with metreleptin led to "rapid change in eating behavior, a reduction in daily energy intake, and substantial weight loss". Leptin is produced primarily in the adipocytes of white adipose tissue.

Leptin circulates in blood in free form and bound to proteins. Leptin levels vary exponentially, not linearly, with fat mass. In humans, many instances are seen where leptin dissociates from the strict role of communicating nutritional status between body and brain and no longer correlates with body fat levels:.

All known leptin mutations except one are associated with low to undetectable immunoreactive leptin blood levels. The exception is a mutant leptin reported in January which is not functional, but is detected with standard immunoreactive methods. Predominantly, the "energy expenditure hormone" leptin is made by adipose cells , thus it is labeled fat cell-specific.

In the context of its effects , it is important to recognize that the short describing words direct , central , and primary are not used interchangeably. In regard to the hormone leptin, central vs peripheral refers to the hypothalamic portion of the brain vs non-hypothalamic location of action of leptin; direct vs indirect refers to whether there is no intermediary, or there is an intermediary in the mode of action of leptin; and primary vs secondary is an arbitrary description of a particular function of leptin.

In vertebrates, the nervous system consists of two main parts, the central nervous system CNS and the peripheral nervous system PNS. The primary effect of leptins is in the hypothalamus , a part of the central nervous system. Leptin receptors are expressed not only in the hypothalamus but also in other brain regions, particularly in the hippocampus. Thus some leptin receptors in the brain are classified as central hypothalamic and some as peripheral non-hypothalamic.

Generally, leptin is thought to enter the brain at the choroid plexus , where the intense expression of a form of leptin receptor molecule could act as a transport mechanism. Increased levels of melatonin causes a downregulation of leptin, [82] however, melatonin also appears to increase leptin levels in the presence of insulin , therefore causing a decrease in appetite during sleeping.

Mice with type 1 diabetes treated with leptin or leptin plus insulin, compared to insulin alone had better metabolic profiles: Leptin acts on receptors in the lateral hypothalamus to inhibit hunger and the medial hypothalamus to stimulate satiety. Thus, a lesion in the lateral hypothalamus causes anorexia due to a lack of hunger signals and a lesion in the medial hypothalamus causes excessive hunger due to a lack of satiety signals. The absence of leptin or its receptor leads to uncontrolled hunger and resulting obesity.

Fasting or following a very-low-calorie diet lowers leptin levels. Leptin binds to neuropeptide Y NPY neurons in the arcuate nucleus in such a way as to decrease the activity of these neurons. Leptin signals to the hypothalamus which produces a feeling of satiety. Moreover, leptin signals may make it easier for people to resist the temptation of foods high in calories. The NPY neurons are a key element in the regulation of hunger; small doses of NPY injected into the brains of experimental animals stimulates feeding, while selective destruction of the NPY neurons in mice causes them to become anorexic.

Once leptin has bound to the Ob-Rb receptor, it activates the stat3, which is phosphorylated and travels to the nucleus to effect changes in gene expression, one of the main effects being the down-regulation of the expression of endocannabinoids , responsible for increasing hunger. It modulates the immune response to atherosclerosis, of which obesity is a predisposing factor. Exogenous leptin can promote angiogenesis by increasing vascular endothelial growth factor levels.

Hyperleptinemia produced by infusion or adenoviral gene transfer decreases blood pressure in rats. Leptin microinjections into the nucleus of the solitary tract NTS have been shown to elicit sympathoexcitatory responses, and potentiate the cardiovascular responses to activation of the chemoreflex.

In fetal lung, leptin is induced in the alveolar interstitial fibroblasts "lipofibroblasts" by the action of PTHrP secreted by formative alveolar epithelium endoderm under moderate stretch. The leptin from the mesenchyme, in turn, acts back on the epithelium at the leptin receptor carried in the alveolar type II pneumocytes and induces surfactant expression, which is one of the main functions of these type II pneumocytes. In mice, and to a lesser extent in humans, leptin is required for male and female fertility.

Ovulatory cycles in females are linked to energy balance positive or negative depending on whether a female is losing or gaining weight and energy flux how much energy is consumed and expended much more than energy status fat levels. When energy balance is highly negative meaning the woman is starving or energy flux is very high meaning the woman is exercising at extreme levels, but still consuming enough calories , the ovarian cycle stops and females stop menstruating.

Only if a female has an extremely low body fat percentage does energy status affect menstruation. Leptin levels outside an ideal range may have a negative effect on egg quality and outcome during in vitro fertilization. The placenta produces leptin. Leptin is also expressed in fetal membranes and the uterine tissue.

Uterine contractions are inhibited by leptin. Immunoreactive leptin has been found in human breast milk; and leptin from mother's milk has been found in the blood of suckling infant animals. Leptin along with kisspeptin controls the onset of puberty. Leptin's ability to regulate bone mass was first recognized in