Blood Tests for Menopause (The Midlife)

4 minute read

One of the most common questions that we hear is, “How will I know if I am in menopause?” As you likely already know, that is not a simple yes-or-no question.

Menopause is defined clinically as 12 months of amenorrhea or absence of menstruation. That seemingly straightforward definition, however, masks a complex condition affecting millions of people. With an average age of onset of 47 years old, perimenopause—the transition period from fertility to menopause—can only be diagnosed in retrospect by considering a set of wide-ranging, somewhat vague symptoms.

Given the ambiguity and interpretation required in menopause diagnosis, a simple test that could definitively state whether someone has reached menopause or not would be extremely helpful for clinicians and patients alike. Medical practitioners can use some hormone tests to gather information about your reproductive status, but none provide the definitive answer we’d like them to.

This article was written for The Midlife. View the entire original here:


Why do we wake up feeling cold? (McGill OSS)

1 minute read

A few different bodily processes in humans follow a stable, roughly 24-hour cycle. For example, the cortisol and melatonin levels in our blood. Physical parameters like your blood pressure and heart rate too.

Also under a circadian cycle is our core body temperature. We reach our minimum temperature about halfway through our sleep cycle. By the time we wake up, our bodies have warmed up slightly, but often not yet to our typical body temp.

So, we wake up feeling cold because we are cold. From a normal body temperature of 36.4-37.2 °C (97.5-98.9 °F), normal circadian fluctuations can take us up or down about 1 ˚C. It might not feel like a lot, but remember that most doctors consider fevers to start at 38 ˚C.

Interestingly, there seems to be some variation in when we reach our minimum temperature during the night. A 2001 study measured the temperatures of 172 young men and women and sorted them according to their self-declared status of “morning person,” “evening person,” or “neither.” They found that morning people hit their minimum temps after an average of 3.5 hours, compared to 5.02 hours for neither types and 6.01 hours for evening types. Since individuals tend to feel more alert and perform better on cognitive tasks at higher body temperatures, these differences in the circadian rhythm of body temperature may be one reason some of us struggle to wake up and feel alert immediately.

Image source:

This article was written for the McGill Office for Science and Society. View the original here:

Will Wearing A Hat Make Me Go Bald? (Skeptical Inquirer)

10 minute read

While losing the hair on our heads doesn’t have any serious medical implications on its own, it can be seriously damaging to our psyches. Studies have shown that both women and men with alopecia, or hair loss, experience increased stress, diminished self-esteem, and other negative psychological effects.

Some of us live in fear of our part widening or our hairlines receding. Others have made peace with their eventual journey to becoming a Patrick Stewart lookalike. Either way, you’ve likely heard a lot of unsubstantiated claims about behaviors that can cause baldness. As usual, some can be dismissed outright (no, masturbating won’t make you go bald), but some bear further investigation.

Read the entire article here:

How Do You Like Your Salmon?

4 minute read
Originally posted here:

If you’re not particularly salmon savvy you may be under the impression that “salmon” is an individual species of fish, like how a black bear is an individual species of bear. That, however, is not true of our fishy friends. In fact, there are two main divisions of salmon: Atlantic and Pacific.

Atlantic salmon are big fish found in the northern Atlantic Ocean weighing 8-12 pounds when fully grown. Their meat is known to taste very mild and is generally cheaper than other types of salmon, due to the fact that nearly all of the Atlantic salmon commercially available today is farmed.

Climate change, human colonization, habitat destruction, and overfishing have decimated the wild populations of Atlantic salmon that were once abundant throughout the northern Atlantic. Lake Ontario was once home to this fish, but by 1900 the population was completely extinct. While there are still wild Atlantic Salmon alive and swimming, their capture is strictly regulated, hence the need for fish farms to fill this void.

What about Pacific salmon? Well, its name is a misnomer, since there isn’t one species of fish called Pacific salmon, but rather seven different species of salmon who live in the pacific: Sockeye, Chinook, masu (found mainly near East Asia), pink, Coho and Chum. While the Pacific salmons have suffered population losses due to humans and climate change, their numbers haven’t been decimated to the extent of the Atlantic salmon, so, wild-caught Pacific salmons are still commercially available.

Chinook (also called King) salmon are the largest of the Pacific salmons, weighing between 20 and 135 pounds. They’re known for being fatty, making them of value to chefs, and also quite pricey, due to their general rarity amongst fish. If you’re after something a little cheaper but still fat-filled, the Coho might be for you. At roughly 20 pounds in size, it is often cooked whole. Your low-fat salmon options include the lesser-known Chum or pink salmons, both quite small and low in fat, as well as the well-known, medium-sized, and bright pink Sockeye.

Whichever type of salmon you choose to eat though, you’ll want to find out where it was caught and whether it was farm-raised or wild-caught. Not for culinary purposes, since at least one study found that farmed salmon was as acceptable to eaters as wild salmon, but rather for health ones.

Quite a few studies have examined the levels of contaminants like PCBs (polychlorinated biphenyls), PBDEs (polybrominated diphenylethers), PAHs (polycyclic aromatic hydrocarbons) and mercury, and the results have not been confidence inspiring.

2001 study found that farmed salmon showed higher levels of PCBs, PBDEs, DLCs (dioxin-like compounds) and other chlorine-containing pesticides that pose significant health risks to humans. Similarly, a 2004 study found high levels of organochlorine contaminants in farmed fish and found that farmed salmon originating in Europe had much higher contaminant concentrations than salmon originating in North America or Chile.

The contaminants seem to get into the salmon through their food. Commercially available salmon feeds are extremely high in contaminants like PCBs and PBDEs, likely due to being made from small fish who themselves harbour high concentrations of contamination.

Interestingly enough, mercury, the contaminant we are used to hearing about in fish, is not an issue for either wild or farmed salmon. One study found that there’s less mercury in B.C. raised salmon than other foods like eggs, honey or vegetables.

Several studies have found that as few as one meal per month of farmed Atlantic salmon can expose the eater to contaminant levels that exceed those set by governing bodies like the World Health Organization. To reach a similar level of contamination by eating wild-caught salmon alone would take more than 4-16 meals per month. You can see a representative chart of this data (based on the United States Environmental Protections Agency’s guidelines) below.


Fish farms can also have devastating environmental consequences due to antibiotic use, waste accumulation, disease spread, escaped fish and more. These effects are bad not only for the surrounding oceans but for the fish too. Infections like sea lice can cause fish extreme pain or even kill them, and the genetic disorders common in farmed fish like curved spines or malformed jaws can severely harm their welfare.

So, what does this all mean for those who feed on fish?

You should keep in mind the potential risks of eating farm-raised salmon while grocery shopping and remember that you can minimize your exposure to these contaminants by choosing salmon that is either wild-caught or farm-raised in North America whenever possible.

If you’re eating salmon mainly for the omega-3 fatty acids, I have some good news and some bad news. The good news is that there are several non-meat sources of omega-3s, such as flax, chia, and hemp seeds, flaxseed oil, and eggs. The bad news is that many of the supposed health benefits of omega-3s have been largely overblown. Our own Dr. Christopher Labos has writtenabout omega-3’s ineffectiveness in preventing cardiovascular events and quite a few Cochrane reviews have found no benefits from fish oil for many conditions including ulcerative colitisasthmaCrohn’s diseaseallergies in children and dementia.

Using Imodium as an Opioid

Originally published here:

The drug marketed as Imodium, loperamide, has found a new, unintended use. While traditionally used for relieving diarrhea, some drug users are now turning to loperamide to either relieve the symptoms of opioid withdrawal, or achieve a high. Loperamide is an opioid receptor agonist, meaning it is very effective at activating opioid receptors, but capsules of Imodium contain very little of loperamide. A normal dose for an adult is 2 capsules, or 4 mg of loperamide, with the maximum dose capping out at 8 capsules, or 16 mg. Forums online cite drug users as recommending a minimum of 100 mg, or 50 tablets to achieve the euphoric high they’re searching for, and some users have taken as many as 200 capsules, or 100 mg. Such a high dose is necessary for psychoactive effects because loperamide essentially does not pass the blood brain barrier, which prevents it from affective the central nervous system at low doses. At these high doses though, users are at a high risk for death due to cardiotoxicity– a dysfunction of the electrical systems of the heart, or damage to its muscles. Naloxone, the main emergency drug in opioid overdose, can treat symptoms like decreased respiration function or unconsciousness, but it is unable to reverse the damage to the heart that loperamide may cause. Not to mention that high doses of Imodium will cause an extreme version of its intended effect- lack of bowel movements. Many users of loperamide are actually trying to treat their opioid withdrawal symptoms, in an attempt to eventually get clean, but do not realize the significant risk associated with such high doses of Imodium. Part of the reason loperamide is so dangerous is its wide availability. Any drug, corner or grocery store will carry it, and there is no limit of the number of packages bought, or the age for purchasing it. Indeed, recent reports have called for placing it under restrictions similar to those affective cough medicine in America.

How to Make the Healthiest Cup of Tea

Photo by Matteo Zamaria
Originally published here:

grew up with British grandparents who probably averaged 5-7 cups of tea a day- a routine I picked up sometime around the age of 10. I never considered though that tea could be good for me! We’ve written quite extensively on tea and it’s many proposed benefits, but despite all the pseudoscience about tea curing cancer or keeping you young, it is worth it to note the compounds that are found in teas, that are truly helpful to humans.

L-theanine is an amino acid analogue to glutamate, the most abundant excitatory neurotransmitter in the brain, and is also responsible for the umami taste found in green tea. Some studies have found that it favourably affects stress responsesmemory and attention span, with special research attention being payed to the positive effects on cognition that substances containing both theanine and caffeine have.  The catechins can be found in tea and are antioxidants, and have been found to help lower blood pressure (especially when systolic pressure are over 130 mm Hg), and may help regulate blood flow in humans. A recent study found that catechins may favourably effect cholesterol as well.

As with everything however, it doesn’t matter how helpful a compound is if there isn’t a relevant dose of it present. A 2011 study looked at the L-theanine in teas, and found black teas to contain the most, ~24 mg/200 ml, and green tea the least, ~8 mg/200 ml. This study also found that adding milk to tea caused a noticeably decrease in theanine content, and that in general, the longer you brewed your tea, the more theanine it contained. Most supplement bottles seem to recommend taking 200-400 mg per day, or the equivalent of about 8-16 cups of black tea, or 25-50 cups of green tea. That’s a lot of tea, even for me

If you do want to get the most out of your tea however, you’re in luck! A lot of research has looked at the most effective way to extracting theanine and catechins from tea leaves, but the results are… interesting. A 2011 study found that steeping quite a fine grind of green tea leaves in 80 °C water for 30 minutes, using a 20:1 ml/g water to tea ratio yielded the best results. For reference, most cups of tea are made with about 200 ml of water to 2 g of tea- a 100:1 ml/g ratio. I just don’t know that I want to drink a cup of tea that strong, even for nutritional benefits.

A 2012 study suggested a slightly different method for tea compounds- microwaving. By placing a tea bag in boiling water for 30 seconds, then microwaving it for 1 minute, the authors were able to improve the extraction of catechins by 18%, though the theanine extraction was not affected. If you’re anything like me however, your heart skipped a beat when I mentioned microwaving tea. Let me assure you however, having tried the described brewing method, it’s not so bad. Not as good an old-fashioned steeping, but not terrible. Keep in mind though, that even in this improved method, only 61 mg of catechins per g of tea, and 10 mg of theanine per g of tea are being extracted. In cup of tea made with 2 g of leaves, that’s ~ 122 mg of catechins and 20 mg of theanine per cup. So if you’re hoping to use tea instead of supplements, I’d still recommend black varieties, and maybe sticking close to a bathroom (my Nana always said, tea goes right through you).

Under the Microscope: Eyelashes

Originally posted here:

Eyelashes exist to keep dust and debris and bugs from entering our eyes, but in our modern day, they have come to be objects of beauty, enhancement and envy. While the Hadza people of Tanzania famously trim their eyelashes for beauty purposes, for most of us, long eyelashes have come to be an object of desire.
Most mammals have eyelashes (and a few birds too!) but they can be troublesome for humans, dogs and horses. There are quite a few conditions that can affect the eyelashes, so I will only name the most interesting ones.
Distichia involves eyelashes growing from parts of the eyelids they are not supposed to (in dogs this includes eyelashes growing underneath the eye since dogs do not have bottom lashes like humans!).
Trichiasis is the leading cause of infectious blindness in the world, and occurs when eyelashes grow towards the cornea, rubbing it and causing infections. This condition is especially common in certain dog breeds, although it can usually be managed through regular trimmings.
Madarosis is characterized by the loss of eyelashes or brows and can be caused by infections like leprosy or HIV, chemo drugs, autoimmune conditions like lupus, or a zinc deficiency.
Of course, you may be unhappy with your eyelashes, although there is nothing medically wrong with them. In that case, you have got some options available to you. There are the fairly common false eyelashes and eyelash extensions, but there is also the semi-permanent option of a lash dip. This procedure will run you upwards of $100, and involved applying a black gel, and sometimes silk extensions, to your lashes that sets and stays for about a month.
If these temporary solutions are not right for you, there is always eyelash transplants. For this, doctors take about 60 follicles of hair from your head and transplant them into your eyelash area. It is done as an outpatient procedure, and only takes 2-3 hours, although it will cost you upwards of $3000. Because these hairs will be head hair, not eyelashes, they will not engage in the normal 7-8 week grow-then-fallout cycle of eyelashes, so you will have to trim and curl them to keep them looking good.
There is an option if you would rather try to grow your own lashes thicker. Bimatoprost (sold under the names Lumigan and Latisse) was originally developed to treat high pressure in the eye, but patients using it reported their eyelashes growing thicker and longer. It is used as an eyedrop that is applied to the base of the lash area, and seems to work quite well, although some patients report the skin around their lashes darkening after use.

BioSil: Can it Really Help Thicken Your Hair and Nails?

Originally published here:

The ads for BioSil look and sound like every other supplement ad. There are bold claims like “promotes unbreakable nails” (I’m pretty sure that’s impossible); references to science like “molecular biologists have pinpointed the key structural protein…” and “your own DNA fingerprint”; and a blond celebrity (Christie Brinkley) smiling while talking about how this product, in particular, has changed her life.

The BioSil website features the familiar refrain “This statement has not been evaluated by the Food and Drug Administration” after every statement about their product, as well as snazzy scientific-looking pictorial representations of what it can do for you.

BioSil is manufactured by Natural Factors. Their site features images of sprawling fields and a cross-section of a grassy patch complete with worms. Everything about it inspires thoughts of nature, because natural is always better, right?

Too bad their site also says “You should not use the information on this site for diagnosis or treatment of any health problem or for prescription of any medication or other treatment.” I would definitely call a supplement for “Rejuvenating your hair, skin, and nails” a treatment, but what do I know?

BioSil’s advertisements, bottles and website make three main claims:

  1. Thickens and strengthens hair
  2. Improves skin elasticity and reduces wrinkles
  3. Strengthens nails

The active ingredient in BioSil is choline-stabilized orthosilicic acid (ch-OSA). Orthosilicic acid is just a silicon atom surrounded by four hydroxide (OH) units, but it is unstable on its own. Enter choline. Choline is an essential nutrient for humans that most of us consume more than enough of every day (it’s found in everything from cauliflower to tofu to chicken to almonds). In BioSil, choline serves to stabilize the orthosilicic acid.

BioSil’s website constantly references clinical trial results, so I read the two trials in question. It’s important to note that we can’t take these studies’ conclusions at face value. Not all studies are created equal. There are a plethora of issues that can hide in a study’s design that could call its conclusions into question. We need to evaluate the design and procedures of a study to know whether we can trust its results. That’s not always an easy task, so let me help.

The first study involved 48 middle-aged, white, healthy women with fine hair (as determined by the study’s hairdresser). 24 of the women were given a placebo, while 24 were given 10 mg of ch-OSA orally for 9 months, during which they did not heat or colour-treat their hair. The 45 women who finished the study had the diameter and tensile strength of their hair measured at the beginning and end of the treatment.

As for the results, well, they’re pretty confusing. I mean look at this:

“the elastic gradient decreased in both groups, but the change was significantly smaller in the ch-OSA group (-4.52%, P = 0.027) compared to the placebo group (-11.9%).”

What does P = 0.027 mean? Let me try to explain.

When a scientist writing a study says that something is significant, it is not the same as when I yell at my TV that the colour of the Monster’s hair on The Masked Singer is significant. Significance in science actually refers to statistical significance, which is measured with something called a p-value.

It’s a controversial way to measure significance but has been something of a standard for a long time (though that is slowly changing). You can click below to read about how p-values work and why they are so confusing, but to evaluate this product all you need to know is that if something is statistically significant, we can say that it is meaningfully different from something else.

For example, we could take a hair sample from someone in the ch-OSA group at the beginning and end of the 9-month period and compare them. A statistically significant result would mean that they are significantly different, i.e. that the thickness of the hair changed in those 9 months.

We could also compare the hair of someone using ch-OSA to the hair of someone using a placebo at the end of the 9 months. A statistically significant result here would mean that whatever happened to the hair with ch-OSA did not also happen with placebo.

Almost every experiment has two hypotheses. Yeah, two. The null hypothesis is the status quo, the prediction that nothing will change. By finding a significant p-value you disprove the null hypothesis. In the Biosil study’s case the null hypothesis is that there was no difference between the effects of the placebo and the ch-OSA. The other hypothesis is the alternate hypothesis, the prediction for the effect your treatment will have. By disproving the null hypothesis, you can conclude that the alternate hypothesis may be confirmed. In this study’s case it’s that the ch-OSA supplement improved hair strength and cross-section more than the placebo

So how do we decide which hypothesis fits with our study results best?

The p-value!

Often times the seemingly magical target to match or surpass is a p-value of 0.05.

That tells us that there is only a 5% chance of obtaining the data we did, or data more extreme than ours if the null hypothesis is true.

In our case a p-value of 0.05 would mean that there was only a 5% chance of getting our data, or data showing even more difference between the placebo and ch-OSA if the placebo and ch-OSA really did have no difference in their effects.

Why 0.05? Because that is what scientists have decided. They could have decided something else, and many others do use a different value. But 0.05 remains the usual p-value threshold of significance.

Looking at the study results we can see that the decrease seen in the elastic gradient of hair was significantly smaller in the ch-OSA group than in the placebo group. This would imply that the ch-OSA helped the hair stay stretchy.

But, we can also look at the yield extension of hair, and see that it was significantly increased for both the placebo group and the ch-OSA group. This would imply that it was not the ch-OSA that caused the improvement in yield extension.

Looking at hair diameter (the literal hair thickness) we can see that the hair of those who took the placebo did not significantly increase, whereas the hair of those who took ch-OSA did. So that is a good mark in ch-OSA’s book, right?

Well, it is not as simple as proving significance. Something of concern in these results is the considerable amount of overlap between the placebo’s effects and the ch-OSA’s effects.

Take a look at the graphs below. I’ve shown the range of results for the ch-OSA group in yellow, and the range of results for the placebo group in blue. Where there is green means that they overlap. 

The majority of each coloured section is green.

This means that there was quite a noteworthy amount of people in the ch-OSA group who experienced the same effects as the placebo group, and vice versa.

Do you really want to pay $25.99 plus tax per month for the chance to be in that little yellow bit?

There is another thing we need to remember when looking at these results: statistical significance does not always equal practical significance.

Those who took the ch-OSA saw a statistically significant increase in their hair diameter, sure, but did they notice it in the mirror, shower or at the hairdressers? Did their hair feel thicker to them? It is possible that the result was statistically significant but that, if asked, participants would say their hair felt no thicker to them, meaning that it was not practically significant.

Do you really want to pay $25.99 plus tax per month for results you can’t even see?

We can evaluate the practical significance of a result through something called the effect size. This measures the magnitude of a phenomenon and would give us an idea not just whether hair thickness improved but also by how much. Sadly, this study does not report an effect size (although judging by the percent increases in diameter of hair, I would guess that it is likely quite small).

So, can ch-OSA make your hair thicker? Maybe. But also, maybe not. And probably not by that much.

As for the other study the product cites, well, I’ll skip explaining the analysis of this one and cut to the chase.

The second study showed that ch-OSA actually decreased skin hydration, although it did very slightly improve skin roughness, nail brittleness and hair brittleness. The problem again is one of effect size. Looking at nail brittleness, participants had the brittleness of their nails ranked from 0 (not brittle) to 3 (severely brittle). With ch-OSA treatment their brittle scores did decrease, but by very little.

So, can ch-OSA help your skin be smoother, your nails be stronger, or your hair be thicker? If you are a middle-aged, healthy, white woman who does not treat her hair, maybe. A teensy bit. But if you are anyone else, we have no evidence to suggest so.

Under The Microscope: Sea Salt VS Table Salt

Originally posted here

Photos 1 and 2 show sea salt, while photo 3 shows table salt.
While they may taste different to the discerning chef and their crystals may look different under the microscope, table salt and sea salt are both essentially just sodium chloride. While sea salt does contain some other minerals, like calcium chloride or potassium sulphate, it is still made up of 90% or more sodium chloride.
Both sodium and chloride ions have important functions. Sodium regulates blood pressure and plays a role in transmitting messages between nerves and muscles while chloride is a component of hydrochloric acid needed for digestion.
The job of maintaining the right concentration of minerals in the blood falls to the kidneys. If blood levels of sodium chloride rise from the ingestion of too much salt, the kidneys will excrete less water in order to dilute the blood and maintain the proper salt concentration. This, however, has the effect of increasing blood volume which can lead to increased blood pressure and swelling in tissues as water leaks out of the bloodstream.
Thirst often accompanies a large intake of salt because water will also be drawn out of cells to help maintain the right concentration of salt in the bloodstream. This is why eating salty foods can lead to both thirst and dehydration! And it makes no difference whether it is table, sea, iodized or Himalayan salt.
The current recommendation is that sodium intake bekept under 2300 mg a day (that is 6000 mg of sodium chloride or roughly one teaspoon) although there is some controversy about whether people with normal blood pressure have to restrict salt intake. Some studies have actually shown that people who consume less than 3000 mg of sodium per day are at greater risk for heart disease than people with an intake of 4000-5000 mg. Most of the salt in the diet comes from consuming processed foods rather than the salt shaker. A single slice of pizza can contain as much as 1000 mg of sodium.