Fingerprick Blood Sugar Tests: How They Work and Why We Still Use Them

Originally published here: https://mcgill.ca/oss/article/health-technology/fingerprick-blood-sugar-tests-how-they-work-and-why-we-still-use-them

We are living in the future. We have robotic personal assistantswatchesthat replace credit cards, phonesthat recognize our faces, and self driving carsare just around the corner. But for all our advancement, patients with diabetes still need to stab themselves multiple times a day to check their blood glucose levels. There has to be a better way, right?

The history of glucose meters starts in 1956 with Leland Clark presenting a paper on an oxygen electrode, later to be renamed after him. Six years later the Clark electrode had been developed, with the help of Ann Lyons, into the first glucose enzyme electrode. These early glucose meters were large, bulky and only used in hospitals. It wasn’t until 1981 that at-home monitors were popularized, sold on the market by the same names you’d recognize today: Glucometer and Accu-chek.

These glucose meters worked by a method still used today that’s quite similar to how breathalyzers detect blood alcohol content. Electrons are transferred from the glucose in blood through molecules until it reaches the electrodes in the glucometer. These moving electrons create an electrical current proportional to the amount of glucose in the blood, and the number appears on the monitor.  

But what if we could measure our blood sugar without having to prick our fingers?

A lot of research and development has gone into that very idea.

Instead of measuring the glucose in blood directly, attempts have been made to measure the glucose in other fluids. Urine tests have been available for much longer than even blood tests but visiting a bathroom every time you need to test your sugar is far from ideal as those with type 1 diabetes may need to test their sugar up to 12 times a day!

New technologies are looking at using tears. Since these fluids are naturally external to the body their measurement needs no needles, something that would decrease the cost of testing and likely increase the reliable tracking of patients’ blood sugar.

Google notably prototyped a contact lens in 2014 that would contain the chips and sensors to measure sugar levels and either change colour accordingly, or transmit that data to an external device. Because of the low volume of tears, the lenses need to be exceptionally accurate. Reliable relationships between the glucose in tears and in blood need to be established and contact lens solution that doesn’t inhibit the lenses needs to be developed.

A few other technologies have been investigated for non-invasive blood sugar testing. A device using near-infrared spectroscopy that would shine light through the earlobe to sense glucose was prototyped, but required a lot of measurements (like earlobe width and blood oxygen levels) to calibrate (though a similar product has been sold outside of the US and Canada). Scientists have attempted to create devices that would pull glucose out from the blood through the skin, using chemicals or electrical currents, as well as devices that would measure blood sugar via polarized light measurements, but at least as of yet, none of these devices have been commercially available in Canada. 

One product that may soon be seen on market is Glucair, which functions similarly to a breathalyzer. It analyzes the acetone present in your breath to take a measurement of your blood glucose level. This system could be made quite small, like modern breathalyzers, and would require no finger pricking or needles of any kind. 

For now the best alternative to finger prick tests are continuous glucose sensors. They consist of a needle that is embedded in the skin that can take blood samples very often, and the circuitry to measure the glucose content. The results are seen by scanning the sensor with a receiver, a smartphone, or via bluetooth connection. They give live results and can last up to 7 days, but tend to be very expensive, given the disposable nature of the inserts, and aren’t always covered by insurance like glucometers are. 

In Canada there are a few neat options available. The Freestyle Libre is what’s called a flash glucose monitoring system. The small sensor is inserted into the skin and worn for 14 days, and can be scanned whenever needed by the receiving decide to get blood sugar levels. The Dexcom G5 is also a small sensor that can be worn for 10-15 days, but it transmits wirelessly to your smart devices. This makes it especially useful for parents or caretakers wanting to monitor someone else’s glucose levels.

(Click here to view a higher resolution version of this image)

Continual monitoring allows greater accuracy in insulin doses and allows a patient to provide more information about their blood sugars to their doctors. Ideally continual sensors will also be able to communicate directly with insulin pumps, so that type 1 diabetics can receive their correct dose without needing to finger prick first.

Considering how far we’ve come since the advent of blood glucose monitoring in the 1960s, I have faith continuous and non invasive technologies are coming. It’s really just a question of how many needles diabetics will have to endure before they do.

Can Bitter Melon Treat Type 2 Diabetes?

Originally posted here: https://mcgill.ca/oss/article/health-quackery/can-bitter-melon-treat-type-2-diabetes

What on Earth is bitter melon?

Good question. I certainly didn’t know before researching this article. Let’s start with some basics.

Momordica charantia is a fruit-bearing plant found in Asia, Africa and the Caribbean. It’s also known as bitter melon, bitter gourd, bitter squash, balsam-pear, karela, kugua or yeoju. It looks and tastes somewhat like a cucumber, and is used for cooking, beer brewing and as a medicinal ingredient for treating everything from diabetes to constipation to respiratory conditions.

Considering that, as of 2015, 3.4 million Canadians lived with diabetes, effective treatments for type 1 or 2 diabetes are highly sought after. Type 1 diabetes is treated with a variety of fast- and slow-acting insulin injections, and with the exception of injection-site reactions and allergic reactions, these are quite effective and safe, if very expensive. But treating type 2 diabetes is much more complex.

Where type 1 diabetes arises from a body’s inability to produce insulin, type 2 arises from a body developing insulin resistance, combined with an insufficient amount of insulin production from the pancreas. So, it’s not as simple as giving somebody the insulin they lack.

Instead, treatment for type 2 diabetes usually focuses heavily on proper nutrition and exercise, with some medications used as well. Metformin is commonly used to decrease liver glucose production and increase the cell’s sensitivity to insulin. Other medications can be used to increase insulin release or to decrease insulin resistance, but not all patients respond to these therapies (about 28% of those with type 2 diabetes end up requiring insulin therapy), and many have severe side effects like liver damage and heart failure.

In light of this situation, it’s easy to see why alternative treatments for type 2 diabetes are attractive to those suffering. But can bitter melon actually help, or is it just lowering your bank balance and not your blood sugar?

As with most (all) things, there isn’t an easy answer. Several studies (1,2,3) have found positive effects on some or many of the markers of type 2 diabetes, which include blood glucose levels, insulin levels, and glucose uptake rates. The first study referenced above is a review of 42 randomized controlled trials (RCTs) and 16 non-randomized controlled trials (NRCTs) on natural supplements for diabetes, but not all of those dealt with bitter melon, and the authors don’t specify how many did. The other two studies were performed on rats which, as we know, are not a perfect model for humans.

But for every study finding a positive result, there seems to be two with negative findings. This 2014 review of four RCTs looked at a total of 208 patients and found that bitter melon had no effect on A1C (amount of hemoglobin with attached glucose) or blood glucose levels. This 2015 study with 95 participants confirmed the hypoglycemic effects of bitter melon, but found it offered poor glycemic control compared to glibenclamide (a commonly prescribed medication for type 2 diabetes).

The most comprehensive review of the lot, done in 2012, examined four RCTs, a total of 479 patients, and found that bitter melon offer no difference in glycemic control compared to a placebo or to the medications metformin or glibenclamide.

There is some debate over the effects of the preparation and administration of the bitter melon on the results. In general, it seems that the fresher the better, with fruit smoothies and juices showing the best results, and capsules the worst. But even those best results are no better than a placebo.

There is some good news though. While its use as a diabetic treatment might be a bust, bitter melon shows some potential as an anti-HIV and AIDS drug. While preliminary studies have seemed positive, we’ll need to wait for the human trials to really evaluate these claims. The situation is much the same for bitter melon’s fate as an anti-cancer drug. Only time (and more research) will tell.

As well, throughout these studies no serious adverse effects were reported. If any side effects were experienced they were mild: fever, diarrhea, stomach aches, etc.

So bitter melon is a supplement of questionable use. Perhaps best kept in a kitchen cabinet for cooking, rather than a medicine cabinet for treatment.

Cissus quadrangularis: the Fever Fighting, Pain Preventing, Diabetes Defeating Supplement?

Originally published here: https://mcgill.ca/oss/article/health-nutrition-quackery/cissus-quadrangularis-fever-fighting-pain-preventing-diabetes-defeating-supplement

Cissus quadrangularisis a plant which belongs in the grape family, has red berries, and green or yellow flowers. Cissus quadrangularisis also the name slapped across a lot of supplements that claim to support ‘optimal joint health’, ‘promote healthy bone structure’, and support ‘healthy weight management’. Add in a few anti-ulcer properties, a pain-killing effect and even type II diabetes support, and this all sounds too good to be true. And it is right?

Well, as per usual, there’s some truth to this plant’s claims, and a lot of overblown and overhyped information.

Cissus quadrangularishas been used for centuries in the traditional medical practices of India. It’s used as a pain reliever, and to heal broken bones. Indeed one of its many names is asthisamharaka, which translates to ‘that which prevents the destruction of bones’.

There are a lot of claims about Cquadrangularis(CQ), but we can broadly divide them into a few different groups, its action as an: analgesic (pain relieving), anti-inflammatory, antioxidant, bone growth supplement and weight loss supplement. Let’s unpack these one at a time.

There have been a few studies looking at the potential pain relieving effects of CQ. A 2010 study looked at the ability of CQ supplements to inhibit pain in rats. They compared 50, 100 and 150 mg/kg bwt (body weight) of CQ with 300 mg/kg bwt of aspirin, and found CQ to be more effective than aspirin at 150 mg/kg bwt. A 2008 studylooked at CQs analgesic effects in albino mice, and found that at doses of 250 or 350 mg/kg bwt CQ worked to inhibit both neurogenic pain (pain from damage to nerves) and inflammatory caused nociceptive pain (pain resulting from injury). The extra 100 mg/kg bwt of CQ caused a ~10% increase in pain tolerance, in both types of pain. A 2008 studyechoed the finding that CQ acts as an analgesic, and suggests ‘the analgesic activity may be due to the presence of carotene, phytosterol substances, calcium, sitosterol, amyrin and amyrone’.

Most analgesics also have some anti-inflammatory action, and it seems that CQ is no different. This 2007 study looked at the supplement’s analgesic, anti-inflammatory and venotonic (increasing venous blood flow) effects, specifically in how they may be used to treat hemorrhoids, and rules positively. The same studythat looked at pain in rats also examined CQ’s ability to act as an anti-inflammatory and an antipyretic. As an anti-inflammatory, 150 mg/kg bwt CQ was more effective than 300 mg/kg bwt aspirin for the first 3 hours after administration. After this time, CQ lagged behind aspirin, but only slightly. As an antipyretic, CQ in the doses tested (50, 100, 150 mg/kg bwt) was less effective than aspirin, but still showed ‘marked’ antipyretic effects.

As far as antioxidant action goes, CQ seems to fair quite well. This 2010 studynotes CQ’s efficacy at lowering lipid levels, improving insulin sensitivity and general antioxidant protection. A 2006 study examined CQ’s potential in treating ulcers caused by NSAIDs (like Advil). In doses of 500 mg/kg bwt, CQ was shown to ‘effectively reduce the extant of gastric lesions’ when used before aspirin treatments. The antioxidants in CQ allow it to enhance ‘defence enzymes in gastric mucosal tissues’. It’s theorized that CQ acts by inhibiting the formation of pro-inflammatory cytokines (substances that tell the body to become inflamed), but no studies that I could find seem sure of the mechanism of CQ’s ulcer defence. They do, however, seem fairly sure that it works.

This 2004 study  noted that CQ supplementation caused an increase in mucous secretion in the stomach, and an increased concentration of mucin, the major protein constituent, in that mucous. It also noted a decreased number of shed cells, and an increase in the DNA per mg of mucous, both of which signal healthier stomach lining. Another 2006 studymirrored the ulcer-healing properties of CQ, and suggested that the high β-carotene content of the plant is responsible for its antioxidative properties.

Speaking of healing things, why not bones too? This 2003 studyfound that treatment with 750 mg/kg bwt CQ per day for 3 months caused a significant increase in osteoblastic (bone cell formation) and decrease in osteoclastic (bone cell re-absorption) activity. It suggests that an unidentified anabolic phytogenic steroid is responsible for CQ’s osteoporosis fighting capability. This 2009 studymimics the preventative effects of CQ on bone loss, and postulate that its effect is due to the steroids interacting with estrogen receptors. A different 2009 studygave perhaps the most in depth analysis of CQ’s method of action. It found that CQ activated and sped up the process of turning bone marrow stem cells into osteoblasts (bone cells).

Now for the claim that seems to be the odd one out, CQ’s effectiveness as a weight loss drug. This 2006 studyfound that at daily doses of 1028 mg for 8 weeks, CQ combined with green tea, soy, B vitamins, selenium and chromium reduced ‘weight, % body fat, BMI and, especially, waist circumference of obese and overweight patients, regardless of calorie-controlled diet’. A 2008 studyconfirmed these results, and specifically found that a combination of CQ and Irvingia gabonensis (African Mango) positively affected patient’s weights and other parameters of metabolic syndrome. 

So how can one plant be having this many effects? Well, that remains to be seen. When researching CQ I found an abundance of studies, without an abundance of answers, and I expect more research to be done in the future. We do knowhowever a lot of the constituents in CQ, such as ‘flavanoids, triterpenoids, Vitamin C, stilbene derivatives, resveratrol, piceatannol, pallidol perthenocissin and phytosterols’. We know that ‘the plant contains ascorbic acid, 479 mg and carotene, 267 mg per 100 g freshly prepared paste, in addition to calcium oxalate’, and that ‘the root powder also contain a rich source of mineral elements (mg/100g dry matter): potassium 67.5, calcium 39.5, zinc 3.0, sodium 22.5, iron 7.5, lead 3.5, cadmium 0.25, copper 0.5 and magnesium 1.15’.

We need to be careful though not to fall into a trap of seeing a long list of chemical names and assuming it’s a new wonder drug. Some of these things are known to be beneficial to humans (like vitamin C), others have more debated effects (like resveratrol), and like every drug, dose matters. It doesn’t matter is CQ has pallidol, if it’s not in relevant amounts. Almost every study that I cited here ends with some variation of ‘further work is necessary to isolate active principles and elucidate the actual mechanism involved in the antioxidant activity of this plant’, meaning that even in the face of these results, these studies know that research is crucial to fully understand this supplements, before we can recommend it for humans. Not to mention that the majority of studies mentioned here were performed on rats or mice, and though they’re good human analogues, they are not perfect replicas.

There is also potentially some behind the scenes meddling at play in these remarkable findings. As this 2010 journal letterpoints out, ’at least 3 recently published studies support the safety and effectiveness of CQ for weight loss but lack financial disclosures or funding sources’. It’s a common practice for studies to mention their funding sources, whether they be McGill University, Government of Canada, or the Liquor Control Board of Ontario. Stating where the money comes from for a study allows readers to know if any involved parties have vested interests, as some CQ study authors seem to. The 3 aforementioned studies have an author in common, who holds the patent for Hydroxycut Advanced, a weight loss supplement using CQ. If that’s not a conflict of interest, then I’m not sure what is.

Looking at the studies of CQ, I’d be hard pressed to deny its potential for use in the treatment of a variety of illnesses, but looking at the state of CQ research right now, I wouldn’t add it to my Amazon cart just yet.