You have to hand it to the Florida Citrus Growers. Back 50 years or more they marketed oranges, and orange juice heavily, promoting them as a source of vitamin C. At a time when scurvy was still known and feared, it was a brilliant piece of marketing. Today, still, for many people, think “Vitamin C”, and “OJ” is the first thing that comes to mind.
Plant sources of Vitamin C
Brilliant marketing by the citrus growers, for sure, and it ensured the continuation of the Florida citrus industry. But of course – like all marketing – only true to a point. Of course there are many other fruits and vegetables with high levels of vitamin C. Even a cup of broccoli has as much as an orange, or ½ a cup of juice. One regular kiwi fruit is basically as good as an orange, and the yellow ones are equal to two oranges! If you like tropical fruits, then half a guava beats an orange.
You don’t even have to be as exotic as kiwi and guava. Not so widely grown in gardens anymore, Blackcurrant bushes (Ribes nigrum) are very easy to grow, and produce a big summer crop of sweet black berries that has more than double to Vitamin C content of oranges. In England there is a popular sweet cordial called ‘Ribena’, developed during WWII, when imported food was very scarce. Diluted in water it has 1½ times the Vitamin C content of orange juice, and is given to children as both a cold and a hot drink. The French use a similar syrup called crème de cassis, but they dilute it in champagne! If you are wanted to be self-sufficient for food, it is easy to make your own syrup, and ensure you have lots of vitamin C in winter without using exotic oranges.
The flower garden too has vitamin C for us. Everyone loves roses, but did you know that the ‘hips’ – those green and then red fruits that develop if you don’t remove the dead flowers – are packed with vitamin C. Some roses produce large hips, and if you are interested in using them for Vitamin C, choose ones that do. How do you eat rose-hips? They can be made into a tea, but for more concentration they can also be turned into delicious, fragrant pink syrups, to dilute as a drink or eat on pancakes. Mixed with apples they make a great jelly too.
For something different, a tree called Sweet Southern Cherry, Barbados cherry, or acerola really takes the prize. One cherry-sized fruit has the Vitamin C of 1½ oranges! With at least 2,000 mg of vitamin C in a cup of these, and with adults needing less than 100 mg a day, you are all set with this tree. An easy tree to grow, it is only hardy in zone 9, but one in a pot can be brought in for the winter, so no serious problem growing your own.
Why is Vitamin C so Important?
Humans are unable to create Vitamin C in our bodies, but it is a very necessary vitamin. When you don’t get enough you develop a disease called scurvy. Today there is a resurgence of scurvy, mostly among the poor and homeless, but for most of us it isn’t a problem, since access to fresh fruit and vegetables 365 days of the year is something we can take for granted. It wasn’t always so, which is why scurvy – the disease caused by Vitamin C deficiency – was such a big problem in the past.
Scurvy begins with weakness and sore limbs. Then as it sets in, teeth and hair fall out. Anemia (low red blood cells) develops, wounds don’t eat, and in the end you can die. Historically it was especially a problem for sailors, because without any way of storing fresh food, they lived on bread and maybe some dried meat – no wonder they got so excited seeing land, any fruit or edible plants they might find could be life-savers.
During the great period of sailing ships and voyages around the world, which ran from about 1500 to 1850, being a sailor might have been an adventure, but it wasn’t good for your health. It is estimated that around 50% of sailors died of scurvy on a long voyage – more even than those who died of warfare, shipwrecks, hostile residents of other countries, other diseases or execution for minor infringements of discipline. No wonder sailors were often ‘pressed’ into service – that is, kidnapped.
It wasn’t until 1753 that a Scottish doctor in England’s Royal Navy proved that citrus fruit would cure it, and it took until 1795 for the Royal Navy to start issuing sailors with a lemon juice ration (luckily citrus fruits store fairly well). Other navies were much slower to follow, which is in part why England became such a powerful naval force in the 19th century.
The essential role of vitamin C is mostly about helping our enzymes to work. Specifically it has a big role in the making of collagen, the protein found in cartilage. When you have scurvy, your body literally falls apart. No wonder the disease was so dreadful, and so feared.
But What About Outside Europe?
‘What about’ indeed. Accounts of scurvy usually focus on Europe, but in colder climates in the past, fruit and vegetables were non-existent for ethnic peoples, and remote communities everywhere. Human ingenuity, often through desperation or chance, solved the Vitamin C problem in some ingenious ways, so here are accounts of a few of them.
Native Americans and Vitamin C
Native Americans were not just the hunters and gatherers they were once portrayed as. They were farmers too, but in the north, with months of frozen soil and snow, fresh food wasn’t an option. The risk of scurvy was high, but they had a solution, long before European sailors and explorers.
The Tree of Life
The first account of the Native American solution to scurvy comes from Jacques Cartier. It is easy to forget that the first Europeans to explore and settle in North America were French, pre-dating the Pilgrim Fathers by a hundred years or more. The distances were relatively short, so scurvy shouldn’t have been a major problem. Until Cartier and his boats became stuck in the ice a long way up the St. Lawrence river in 1535, and were there all winter. Sailors sickened and began to die, but luckily Cartier had made relationships with the local tribes. The French were more interested in trade than in settlement, so there wasn’t the same friction as would develop further south. The tribal people fed his sick sailors on a tea made from white cedar (Thuja occidentalis). It contains more Vitamin C than oranges, and his men were saved, to return to France once the ice melted. A grateful Cartier named the plant ‘arbor-vitae’, which means ‘tree of Life’ and took some back to the gardens of the King of France. We still today call it Arborvitae, but how many of us know why? Jacques Cartier went on to found the city of Montreal.
Another source of Vitamin C available for much of the winter to Native Americans is Sumac, Rhus typhina. Widely known for its beautiful fall colors, it is the red clusters of seeds that were used to make ‘pink lemonade’, not just by local tribes, but the settlers quickly caught on too, and began to do the same. Boiled in water, or even just soaked, those colorful seed heads yield a drink rich in the precious vitamin, and a great protection against scurvy during those long northern winters.
Preventing Scurvy in Central Asia
American Indians were not, of course, the only people who knew how to survive in hostile environments. The common shrub called shrubby cinquefoil, Potentilla fruticosa, is popular in gardens, particularly in colder zones, for its long bloom period and charming golden-yellow blooms. The small hairy leaves are not something you would automatically assume were edible – but they are.
Shrubby cinquefoil has an extensive natural range, throughout all of the northern Hemisphere, mainly in arctic and sub-arctic areas, including both North America, colder parts of Europe, and all the way from Russia to China, Japan and Korea.
All through central Asia, in Siberia and also in Tibet, the leaves of shrubby cinquefoil, fresh or dried, are made into a tea called ‘kuril tea’.
The Kuril Islands are a long chain of small, isolated islands that runs from the northern tip of Japan towards Russia (specifically the Kamchatka Peninsula).
The leaves of shrubby cinquefoil have high levels of Vitamin C, exactly how much is hard to find out, because these leaves have also turned out to have rich sources of antioxidants, a much more commercially-valuable product than vitamin C, now that scurvy is so much less common. The tea is widely available, and of course you could easily pick and dry your own leaves.
Why Do Plants Make Vitamin C in the First Place?
There are certainly many other plants that contain Vitamin C, they just haven’t been recognized yet. Since most of the research on vitamins in plants is about all the good they do humans, there isn’t much being done on how they benefit the plants. Don’t imagine they are somehow growing and producing it so that we humans can take advantage of that. It certainly has specific functions in plants, that benefits the survival of the plants. Two possibilities have been shown in the limited research that has taken place, different from the reasons Vitamin C benefits us.
For the plant, one value seems to be that Vitamin C in the chloroplasts, those bodies that do photosynthesis, protects them from high light levels. It’s easy to see that in shrubby cinquefoil, exposed to the high light radiation in arctic regions, this would be beneficial to the plant. White cedar and sumac are also plants of intense arctic light.
The other value seems to be increased resistance to lower temperatures. Many of the fruits that contain it ripen later in the year (citrus too ripen over the winter months), or in colder climates and the presence of Vitamin C could protect them from being damaged by cold before they are ripe.
If we knew more about the value of vitamin C to plants, which might be able to find ways to increase the content and modify the plants we have already to make them richer in it.
So it turns out that oranges don’t have any kind of monopoly on Vitamin C, despite what the marketing gurus would like us to believe.