Think about your digestion. Are you thinking about your stomach right now or did you picture your mouth? Because that’s where starts!
There is literal digestion of carbohydrates that occurs in the mouth through the enzyme “salivary amylase”. But then there are also the neurological triggers caused by different tastes. Although researchers in Columbia have recently found that the “taste map” we were taught about at school is wrong (Barretto R., et al. 2015), we still have the ability to detect 6 main flavours: salty, bitter, sour, sweet, water and umami (protein). The taste receptors (TRs) for these flavours lie throughout the tongue and are not localised to one area. The TRs dedicated to sweet flavours are comprised of one type of protein that is coded for by 3 genes and detects sugar. The TRs for umami (protein) are similarly simple and they detect amino acids (Buchanan et al., 1993). Sour tastes are slightly more complex. They have two receptor subtypes that detects hydrogen ions (responsible for acidity). There is also a receptor for fats and a receptor for salts. All of which are made from one-five genes with one-three subtypes. But then we turn to the bitter taste-receptor family. This is known as the T2R receptor family and it has twenty different subtypes and is coded for by thirty-four genes (McCraty et al., 1998). This gives these TRs the ability to detect over one hundred unrelated, bitter compounds.
Why do the bitter tastes receptors need to be so complex?
The bitter flavour is used as a signal for potential poisoning from the vegetable kingdom. A low concentration of bitterness is tolerable; however, a high concentration can lead to vomiting. How handy if you’ve just consumed poison! Not only are these TRs used to detect poisoning, but they also serve as a trigger for bile secretion and antioxidant enzymes from the liver through the combined action of hormones, such as cholecystokinin, and nerves, such as the vagus nerve. In turn, this increases the efficacy of digestion and the ‘detoxification’ pathway of the liver, while decreasing the rate of digestion and leaving you feeling fuller for longer. It also supports the function of the liver. For the creative-minded out there, I could say that bitter foods ‘tickle the liver into being awake, alive and challenged’. The other benefit of eating bitter food is that it is an appetite-regulating pathway. If our primal selves sense that we might be eating poison, then it makes sense that we are going to want to eat lower quantities when eating a bitter meal. The bitter taste is also an important dietary aspect for diabetic patients (type 2) to utilise because it lowers blood glucose (sugar) levels. (Guido Mase, 2013)
So… bitter flavours help to reduce caloric intake, increase effective digestion and detoxification of the liver and decrease blood glucose. Yet this flavour is an outcast within the Western Diet.
Traditionally, people would forage to supplement their meals. They might add stinging nettle, dandelion, wild rocket or a number of green leaves to a stew or soup. Sweet gums or honey were rare to come across, but when you did they evoked a deeply satisfying sensation. We have discussed bitter foods and how the neurological trigger in the mouth leads to changes in digestion. However, the neurological triggers of sugars largely remain within the mind and do little to activate digestion. This taste makes us feel loved, safe and rewarded, much like a drug and we naturally begin to seek it out. In small doses, this is a beneficial response because it provides energy-dense meals in a (once-upon-a-time, physically) competitive environment. However, as we have moved away from a foraging lifestyle and stepped into a world of supermarkets our ‘small, sweet dose’ has become the main component of our daily diet.
Sweet carbohydrates do little to activate digestion and can pass through the gut like ghosts. They trigger a high blood glucose level but are met in the small intestines with a sluggish enzymatic response. In turn, this leads to pieces of carbohydrates fermenting in the stomach and that leads to gas, bloating and halitosis (bad breath). A sluggish gut also becomes inflamed and the inflammation irritates nerve endings along the gut and ultimately reaches the central nervous system via the vagus nerve. And this, my friends, is partially how the vicious cycle between food and mental behaviours (depression, anxiety etc) begins. But that is a story for another day.
Now that we have been reminded about the importance of bitter foods in our diet I can get to the main point of this article.
Partially as a health professional, but mostly just as a young-adult female, I often hear other women (and sometimes men) saying things like “I’m not going to drink alcohol this week, I need to detox”. Or “I’m going on a 3-day juice fast…I need to detox from this holiday’s junk food”.
These sentences are riddled with misconception. There is nothing we can do to detox ourselves. We have eliminatory organs that are ‘detoxing’ our bodies every day. They do not switch on when we decide we need to ‘detox’ from a binge weekend. They work continuously and relentless to keep our bodies in balance. These organs include the liver, the kidneys, the lungs, the skin and the large intestine. Although we can do nothing to activate the already-working detoxing system, we can lighten the load on these organs so that they function better. If your lungs always seem to be heavy with phlegm, try cutting out dairy. If your skin is always breaking out, try reducing sugar and fat. If you are often constipated, reduce your refined carbohydrates. This ‘lightens the load’ on these organs. It is also a life-long solution that will help you to live better and brighter on a daily basis. It is not a quick ‘detox’ fix that will make you feel better about yourself. Try incorporate the bitter flavour into your diet. Allow it to replace some of the sweet. This will support the function of your liver and, in turn, your large intestine. If these are functioning well you should automatically see an improvement in your skin and your mood.
I realise that bitter foods are so lost in our diet that many of you might not even know where to begin incorporating them into your diet. How about a cup of green tea (without sugar or honey) after a meal? Or try roasting minced dandelion roots in a pan until they are dry and slightly nutty. Store this in an air tight container and use in a coffee plunger whenever you need a cuppa “coffee”!
Alternatively, here is my ‘Forager’s soup’ recipe:
- Forage for a handful of dandelion leaves and a large handful of nettles.
You can place a shopping bag over your hands and pick them straight. When you get home, boil water and pour it into a bowl with a tiny bit of apple cider vinegar (to remove anything unwelcome on our plants…it’s not always possible to avoid pollution and occasional dog wee when foraging now-a-days!). Then cut the nettle leaves straight into the boiling water to avoid stinging yourself. Add the dandelion leaves (it is usually best to harvest in spring but any time is ok).
- Chop up a carrot, a potato, a tomato, a clove of garlic and half an onion.
- Add to a pot with 1 tablespoon of olive oil and lightly simmer until things start to smell good.
- Add the washed, nettle and dandelion leaves to the pot and pour in your water. (I guesstimate when it comes to amounts…so I will leave you to your instincts)
- Add some salt and let it boil until cooked. I normally use a hand blender to make it smooth as I do not particularly like chunky soup (except Scotch broth, which I have experienced for the first time here in Scotland)
Enjoy! Keep your liver, your gut and your mind happy.
Barretto R., Gillis-Smith S., Chandrashekar J., Yarmolinsky D., Schnitzer M., Ryba N., Zuker C. (2015) “The neural representation of taste quality at the periphery”. Nature Publishing Group, a division of Macmillan Publishers Limited. All Rights Reserved.
Buchanan LM., Cowan M., Burr R., Waldron C., Kogan H. (1993) “Measurement of Recovery from myocardial Infarction”. Nursing Research.
Guido Mase. (2013) “The Wild Medicine Solution”. Lake Book Manufacturing Inc, United States of America.
McCraty R., Barrios-Choplin B., Rozman D., Atkinson M., Watkins AD. (1998) “The Impact of a New Emotional Self-Management Program on Stress”. Integrative Physiological Behavioural Science.