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ASPARAGUS MYTHS OR FACTS?

You’ve probably noticed Australian asparagus is available now! It’s in season from September to March, with a smaller supply during summer.

More than 95% of Australia’s asparagus is grown in Victoria, and a serve (about three to four spears), boasts a quarter of your daily vitamin C needs, and provides B vitamins, potassium, and fibre.

Glenn Cardwell Adv. APD reviewed the myths and facts about this nutritious harbinger of spring. Is asparagus really an aphrodisiac? Does it cure cancer? Help if you have a hangover? Cause gout? Here’s what you need to know:

  • Asparagus cures cancer. False. There is a common email hoax suggesting that asparagus cures cancer, without any proof. Vegetables, like asparagus, certainly reduce the risk of getting cancer, but sadly, there is no evidence of a single vegetable curing cancer.
  • Asparagus is an aphrodisiac. False (probably). Asparagus was mentioned as an aphrodisiac in the ancient book The Perfumed Garden, a fifteenth century Arabic manual of erotica, although it may have been written as early as the 12th century. It is claimed that the 17th century herbalist Nicholas Culpepper said that the asparagus “stirs up lust in man and woman”.
    A report from Rutgers University specifically states: “Protodioscin is an aphrodisiac present in asparagus that has been linked to improvement of sexual performance”, yet provides no supporting evidence. There have been two published papers suggesting that protodioscin increases testosterone levels in laboratory animals and humans but there isn’t strong evidence that the asparagus is helpful in the bedroom (Gauthaman 2008; Maheshwari 2017).
    However, if a plate of asparagus makes you amorous, there will be no argument from us!
  • Asparagus is a good source of folate. True. A serve of fresh asparagus can provide over 20% of your needs for this valuable vitamin. Expectant mums need adequate folate for healthy babies, while everybody’s heart and arteries seem to be thankful for plenty of folate in the diet.
  • Asparagus makes your pee smell funny. True (for some people). To make the asparagus plant less attractive to parasites it produces a compound called asparagusic acid. This same compound, when eaten, is metabolised to other compounds that provide the characteristic bouquet of your pee after you eat asparagus (Mitchell 2013). Some people claim they notice the odour of their pee changes to one reminding them of cabbage, vegetable soup or, as you would expect, asparagus.
    It is still not clear which metabolites of asparagusic acid give urine its asparagus smell. Some people don’t produce enough of the odorous compounds to be smelled in urine. Some people don’t have the ability to smell the compounds in urine even when they are present in sufficient amount (called anosmia). This suggests there is a genetic aspect to this (Markt 2016).
    Although we all excrete the same compounds after eating asparagus, reports vary in the proportion of people who can smell the difference. There is a belief that more people from a Chinese background can smell a difference compared to those of a Caucasian background. A well-designed study found that about 1 in 10 people didn’t produce enough compounds to give pee an asparagus aroma, while 1 in 20 could not detect an odour (Pelchat 2011).
    The most recent study of nearly 7,000 US health professionals who ate asparagus revealed that 4 in 10 could detect a urinary odour after eating asparagus, while the other 6 in 10 had asparagus anosmia (Markt 2016).
    Whether or not your pee changes in odour after eating asparagus is all academic really because asparagusic acid and its metabolites are harmless (Mitchell 2014).
  • Asparagus is a diuretic. False. Although some early research 70 years ago suggested asparagus is a diuretic, more recent research does not confirm that asparagus can stimulate excess urine production, nor can it specifically lower high blood pressure (Chrubasik 2009).
    However, as fresh asparagus is high in potassium and low in sodium (salt), like all vegetables and fruit, it will help maintain a healthy blood pressure.
  • Raw asparagus is bad for you. False. In fact, it is likely to have a little more vitamin C and folic acid than the cooked version, because those two vitamins will decline during cooking. Raw asparagus will have a different texture and flavour to steamed or lightly fried asparagus, yet will be equally as nutritious if cooked briefly.
  • Asparagus helps cure a hangover. False. The best cure for a hangover is time and fluids. Alcohol encourages the kidneys to lose too much water so that you will be dehydrated the next morning.
    The asparagus is 90% water so it is perfect to eat as part of your fluid replacement after a heavy night, but you are likely to need a few glasses of water too. Maybe just avoid getting a hangover in the first place?
  • Asparagus is a cause of gout or makes gout worse. False. Foods that are high in purines may cause a flare-up of a gout attack. Asparagus is not high in purines and yet often gets labelled as a food to avoid by gout sufferers. Nowadays, very few physicians would recommend eliminating any vegetable from the diet of someone with gout.
    After reviewing all the evidence about food and gout Dr Choi, Professor of Medicine, Boston, USA recommended the consumption of vegetables, including those with purine, because people who ate the most vegetables had a 27% reduction in their risk of gout, compared to those eating the least amount of vegetables (Choi 2010).
    Another study also found no association between purine-rich vegetables and blood uric acid levels (Zgaga 2012).
    Gout tends to greatly improve with weight control, exercise and the avoidance of alcohol and, possibly, very high purine foods like offal and some seafoods. Often medication is used to alleviate the painful symptoms of gout in joints.
    There is no reason to avoid or limit asparagus in your diet.