Saturday, April 21, 2012
Spotlight Food - Asparagus...
Spring is here, and that means it’s asparagus season! I absolutely love asparagus! Not only is it one of my favorite springtime vegetables but it’s one of my favorite vegetables period. It has such a unique flavor, and works so well in so many dishes. This spring asparagus seems to be everywhere in abundance, and the price is very low - in fact the lowest I’ve ever seen it -, so I’ve been taking full advantage and buying up pounds and pounds of what is usually a rather pricy food. I’ve been making all my favorite asparagus recipes, and new ones too! Utilizing a food I don’t get to eat year round. Truthfully even though it’s usually available throughout the year, it’s never as good as when you get it fresh in the spring. So take advantage!
Aside from it being delicious, asparagus also has the added benefit of being low in calories and low in sodium. It’s chalk full of a bunch of other good nutrients as well, which we’ll get to later, but first I wanted to address a commonly known fact about asparagus. Yes, you’ve guessed it, I’m talking about the urine effect. A lot of people complain that after they eat asparagus their urine smells funny, pungent and even awful. This deters a lot of people from eating it, which I think is silly because who cares if your urine smells after you eat it? Who’s going to smell it but you anyway? And even then you’re only in the bathroom a few minutes! Anyway, the interesting thing is that several researchers have studied this unique effect with the intention of finding out why some people produce foul smelling urine after eating asparagus while others do not. As it happens, researchers from France, China, and Israel discovered that odorous urine after asparagus consumption is a typical human characteristic. Meaning that the majority of humans produce this smelly urine. However only something like 22% of the human population actually has the autosomal genes required to smell it! They figured this out when it was discovered that those who could smell their own stinky urine could also detect the odorous smell in the urine of others, even those who could not smell it themselves. Fortunately both my husband and I fall into the category of ‘it doesn’t effect us’ or ‘we just don’t have the genes needed to smell it.’
So what does this teach us? 1) Virtually everyone has smelly urine after eating asparagus. 2) Just because you can’t smell it doesn’t meant it doesn’t smell. 3) Since virtually everyone is effected in this way, there’s no need to be embarrassed. Suck it up, asparagus is delicious and nutritious so go ahead and eat it!
Asparagus has been eaten and enjoyed both as a vegetable and as a medicine since ancient times. Native to the temporal regions of Europe, North Africa and Asia, it has been eaten in Egypt since 20,000 BP. The use of asparagus as an offering is pictures on Egyptian tablets dating back to 3000 BC. However the ancient Egyptians were not the only ones to enjoy this springtime vegetable. It was also known to the Syrians, and the Spanish as well as the Greeks and the Romans who praised it not only for it’s delicate flavor, but for it’s diuretic properties as well. The Romans would eat it fresh in spring, and dry or freeze it high in the Alps to use in the Feast of Epicurius. There are even recipes for cooking asparagus in the oldest surviving book of recipes, Apicius’s third century AD De re coquinaria, Book Three.
Cultivation of Asparagus began in French Monasteries in 1469, but it wasn’t till the 18th century when it became extremely popular in the country. During the rule of Louis XIV special greenhouses were built for growing asparagus and it was served as a delicacy. It made it’s way to the New World and the United States around 1850.
Asparagus delivers a truly unique blend of anti-inflammatory nutrients that have been shown to be of benefit. Among these nutrients are saponins - including asparanin A, sarsasapogenin, protodioscin, and diosgenin. Sarsasapogenin has been of particular interest in relation to ALS - also known as Lou Gehrig’s Disease) Even though ALS is characterized as a chronic neurodegenerative disease and not currently accepted as an autoimmune disorder, it’s thought that excessive inflammation may play a role in the death of motor neurons in ALS.
In addition to it’s anti-inflammatory benefit Asparagus also offers a wide variety of antioxidant nutrients, such as Vitamins C and E, beta carotene, and minerals like zinc, manganese, and selenium. It may also contain a valuable amount of the antioxidant glutathione (GSH) which is one of the bodies best studied antioxidants. One published study has estimated the GSH in fresh asparagus to average 28 mg per 3.5oz. While other studies have compared the antioxidant capacity of Asparagus with that of cruciferous vegetables such as cauliflower and cabbage.
This is important because anti-inflammatory and antioxidant nutrients are amongst the best risk reducers for chronic diseases such as type 2 diabetes, heart disease and certain types of cancer.
Most of the studies conducted on the anti-cancer benefits of asparagus have been conducted on rats, and mice or on specific cancer cells. For this reason asparagus-cancer research is considered preliminary as it’s not yet been validated by large scale human studies. However the trends in animal and specific cell studies are clear, asparagus as well as asparagus extracts can change the metabolic activity of cancer cell types. These changes are protective in nature and related to better regulation of inflammation and oxidative stress. Cancer cells taken from the liver have been the most studied in this regard.
It’s possible that Asparagus may also have an effect on Leukemia, however the research at this time is poor. The initial thought behind this lies in the fact that leukemia cells need to obtain a specific amino acid called asparagine from other cells or from the blood. If leukemia cells are prevented from obtaining asparagine they may have trouble surviving. Research from the 50's and 60's discovered that the injection of an enzyme called asparaginase into patients with leukemia could result in decreased levels of asparagine in the blood and selective destruction of leukemia cells through asparagine deprivation. Prescription injection of asparaginase enzymes is still used in treatment for acute lymphoblastic leukemia. The reason asparagus has been looked to in this instance is because it contains both the amino acid asparagine, and the enzyme asparaginase as their names suggest, however there is no current research showing a treatment connection between leukemia and dietary intake of asparagus. The only research so far concentrates on the prescription injection of the enzyme medication.
Asparagus also seems uniquely designed to help support a healthy digestive system. With it’s rich fiber content - 3g per 1 cup - and it’s significant protein - 5g per 1 cup - asparagus helps stabilize our digestion and keep things flowing along our digestive tract at an appropriate speed. As opposed to fatty foods that slow down the digestive process or sugars that speed it up. However it’s digestive support doesn’t end there. Asparagus also contains a significant amount of a nutrient called inulin, which has been described by some healthcare practitioners as a ‘pre-biotic.’ Inulin is a special kind of carbohydrate called a polyfructan, and unlike other carbs inulin doesn’t get broken down in the first sections of the digestive tract. Rather it passes undigested through the small intestine and arrives intact in the large intestine where it becomes an ideal food source for specific kinds of bacteria, associated with better nutrient absorption, lower risk of allergy, and lower risk of colon cancer. Due to it’s unique effect on our digestive system it’s no wonder that asparagus has a long history of use in Indian Ayurvedic medicine for treating digestive problems.
While there have been no large-scale human studies researching the effect of asparagus on heart disease and blood sugar regulation, preliminary studies suggest asparagus may be helpful in both these areas of chronic disease. This is due firstly to the incredible vitamin B content of asparagus. Asparagus has proven to be an excellent source of folic acid, and vitamin B1, as well as a good source of vitamin B2, B3, and B6. It also contains B vitamins such as choline, biotin, and pantothenic acid. This is important because B vitamins play a key role in the metabolism of sugars and starches, they are critical for maintaining healthy blood sugar. They also play an important role in regulating homocysteine, and amino acid that becomes a strong risk factor for heart disease if it’s allowed to reach excessive levels. Secondly it’s potential benefit on heart disease and blood sugar can be attributed to it’s asparagus’s fiber content. As it’s well known that intake of soluble fiber has repeatedly been shown to lower the risk of heart disease as well as type 2 diabetes. Lastly, asparagus’s antioxidant, and anti-inflammatory properties are crucial. Both heart disease and type 2 diabetes are considered chronic diseases that develop in relation to chronic inflamation and oxidative stress. Meaning asparagus’s high antioxidant and anti-inflammatory nutrients could help lower the risk of both heart disease and type 2 diabetes.
Studies conducted on persons with Alzheimer’s found that those suffering from the disease had extremely low to no levels of folate in their bodies. Since asparagus is such an excellent source of folate, it could be beneficial both in preventing and treating early stages of Alzheimer’s. However no large-scale human studies have been conducted at this time. Folate is also a crucial nutrient for pregnant woman as it helps protect against birth defects.
Green Asparagus is also a particularly good source of vitamin C, and vitamin C is important in the production and maintenance of collagen, which is the major structural protein component of the connective tissue in the body.
The second century physician Galen described asparagus as being both “Cleansing and healing” which certainly seems true today, as asparagus is considered a diuretic, a mild laxative and a neutralizer of ammonia in the body.
Overall though more research needs to be conducted asparagus seems to have many benefits, and it’s delicious too!
Honestly I love asparagus cooked anyway and in any dish. I love it lightly steamed, grilled, sauteed, stir-fried, roasted, raw, or baked. I love it hot or cold, in soups, stews, salads, pasta dishes, tarts, casseroles, or on it’s own. I love it plain, and by itself, I love it dressed simply or elegantly. I love it with rice or cous cous, I love it as a filling for sushi or even a wrap. It’s even great as part of a tofu scramble. Honestly the ways you can enjoy asparagus are endless, it’s so versatile and it works brilliantly with a wide variety of seasonings. Try it pan fried with shallots, garlic and lime juice. Or try it steamed and drizzled with olive oil, balsamic vinegar, rosemary and minced garlic. Tick it up a notch with a Cajun, or Jamaican rub, or just some good ole’ red pepper flakes. Don’t be afraid to experiment with it!
Happy and Healthy Eating to you!