The Proof Is in the Plaque

It was dental research, not pottery, that offered scientists the first direct proof that humans consumed cow’s milk. In 2019, researchers at England’s University of York analyzed hardened plaque from Neolithic humans in Britain and found evidence that they consumed milk from cows, sheep, and goats around 6,000 years ago. Other similar studies traced milk consumption through the Bronze Age around 3000 BCE.

Most Neolithic people were, however, lactose intolerant; drinking fresh milk could cause severe stomach issues and illness. So researchers believe the dairy traces may have been from cheese or yogurt, which contain less lactose than fresh milk. Young children naturally produce lactase (the enzyme that breaks down lactose) for several years after weaning from breast milk, so it’s also possible that fresh milk served as an important, calorie-dense food for early childhood survival in early farming communities. 

Milk Became a Superpower — for Some

So, did adults also drink fresh cow’s milk? Based on human genetic patterns, researchers think it’s likely. Genetic mutations that allowed adults to digest lactose — called lactase persistence — began appearing around 8,000 years ago, likely because some populations were already drinking fresh milk. The mutations spread most rapidly in Northern Europe, where shorter growing seasons would have made milk a regular and reliable source of calories, protein, and hydration. Cows, in particular, produced higher yields than other domesticated animals, and in regions with cooler climates, milk could stay fresh and more suitable for drinking for longer than it did in warmer regions.

Drinking milk wasn’t just a dietary change — it was part of a much larger shift in human history. Studies show that populations with high milk consumption tended to be taller and heavier, and those who could digest lactose were more likely to survive famines or seasonal crop shortages, giving them an evolutionary edge. Still, the ability to comfortably drink fresh milk as an adult was the exception, not the rule, for thousands of years. In most early societies, milk was processed into cheese or yogurt more often than it was poured, and even today, lactose intolerance remains common in many parts of the world, showing that widespread milk drinking is a relatively recent — and uneven — chapter of human history.

Salt Meat and Preserved Fish

Biscuits alone wouldn’t keep sailors fit and healthy on a voyage lasting weeks or months. Having sources of protein was vital, and these were stocked on board in advance in preserved form. Salted beef and pork (known as salt tack) were a fundamental part of a sailor’s diet, as was salted fish — typically cod, favored due to its low oil content, which made for easier preservation. Salt preservation was one of the few reliable food technologies of the era, capable of keeping meat edible for months. Meat and fish were heavily salted and packed in wooden barrels before departure, and were essential for the success of any voyage. 

Livestock

Not all the meat stored for voyages was preserved. When space allowed, and especially for longer expeditions, ships carried livestock in the form of pigs, goats, chickens, and sometimes cattle, which were loaded aboard to be slaughtered and eaten as the journey progressed. 

The English ship the Golden Hind, on which navigator Francis Drake completed his circumnavigation of the globe between 1577 and 1580, carried livestock that was butchered throughout the voyage, with chickens providing eggs for as long as they could be kept alive. In general, however, livestock didn’t fare well on ocean voyages, and sailors would soon find themselves falling back on salted meat and hardtack. 

Butter and Cheese

Salted butter and cheese, both of which were ideal for long journeys, made hardtack more palatable and provided a much-needed contrast to all the preserved meat. During English explorer Martin Frobisher’s expedition in the 1570s, which sought the Northwest Passage for trade purposes, each sailor had a daily food allowance that included a quarter pound of butter and half a pound of cheese, to go with their pound of hardtack. Later, in 1677, Samuel Pepys, then secretary to the British Admiralty, included cheese and butter in his list of provisions for every sailor in the navy. 

Beer

Keeping stores of fresh water was one of the most logistically challenging elements of any long voyage. Even when stored in sealed barrels, water went stagnant quickly, developing algae, insects, and a foul taste within weeks. The solution was beer. This was a low-strength brew in which the alcohol acted as a mild preservative, keeping the liquid drinkable for far longer than water. Beer is also rich in vitamins, particularly B vitamins, as well as carbohydrates, both of which were needed to supplement a sailor’s diet. A sailor’s ration, including for those serving in the British navy, often included 1 gallon of beer each day.

Fresh Fruit and Veggies

Many sea expeditions set sail carrying fresh fruit and vegetables — but these supplies didn’t last long. While dried peas and beans could keep for extended periods of time stored in barrels, fresh produce such as apples, pears, onions, garlic, and citrus fruits would often perish within weeks. The lack of fresh produce took a terrible toll. From the 15th to 17th centuries, more sailors lost their lives to scurvy — caused by a dietary deficiency in vitamin C — than to war, storms, shipwrecks, or any other diseases combined. It wasn’t until 1753 that Scottish naval surgeon James Lind definitively proved that scurvy could be cured and prevented by consuming the juice of oranges, limes, and lemons, after which citrus juices (often mixed with a little alcohol to prevent spoiling) became a vital part of a ship’s supplies. 

Indigenous Foods

Explorers setting out on overland expeditions faced different but equally serious food challenges. Sometimes, however, they had a far wider array of potential solutions than those available during sea voyages. For example, Spanish conquistadors pushing through the Americas in the 16th century depended heavily on what they could extract — voluntarily or otherwise — from the Indigenous populations they encountered. Hernán Cortés and his men survived portions of their Mexican campaign on maize, beans, and whatever could be seized or traded from local communities. 
Other overland expeditions had fewer options, and in some cases relied heavily on pemmican, a concentrated mixture of dried meat (often bison) and fat traditionally prepared by Indigenous peoples in North America. In 1793, when Scottish explorer Alexander Mackenzie became the first European explorer to cross North America north of Mexico, he relied on pemmican as the core provision of his overland push, supplemented by whatever his party could hunt and fish along the route. Pemmican was arguably the most sophisticated long-distance food technology of the age, being calorie-dense, lightweight, and stable for months — the original energy bar.