Table of Contents
Medical disclaimer
This guide is a general-health document for adults 18 or over. Its aim is strictly educational. It does not constitute medical advice. Please consult a medical or health professional before you begin any exercise-, nutrition-, or supplementation-related program, or if you have questions about your health.
This guide is based on scientific studies, but individual results do vary. If you engage in any activity or take any product mentioned herein, you do so of your own free will, and you knowingly and voluntarily accept the risks. While we mention major known interactions, it is possible for any supplement to interact with other supplements, with foods and pharmaceuticals, and with particular health conditions.
Examine.com does not assume liability for any actions undertaken after visiting these pages, and does not assume liability if one misuses supplements. Examine.com and its Editors do not ensure that unforeseen side effects will not occur even at the proper dosages, and thereby does not assume liability for any side effects from supplements or practices hosted under the domain of Examine.com.
Examine.com does not make any representations, recommend or endorse any specific tests, products, procedures, opinions, or other information that may be mentioned on the website. Reliance on any information provided by Examine.com, Examine.com employees, guest writers, editors, and invitees of Examine.com, or other visitors to Examine.com is solely at your own risk.
How to use
The Examine team has been publishing research on nutrition and supplementation since March 2011. Drawing from all we’ve learned, we’ve designed this Supplement Guide with two aims in mind: helping you decide which supplements are right for you, based on the scientific evidence, and helping you integrate these supplements into synergistic combos.
Primary supplements have the best safety-efficacy profile. When used responsibly, they are the supplements most likely to help and not cause side effects.
Secondary supplements may provide substantial benefits, but only in the right context. A secondary option is not for everyone and not a first pick, but if you read the entry and find that you meet the criteria, consider adding the supplement to your combo.
Promising supplements have less evidence for their effects. They could work or be a waste of money. Keep them in mind, but think twice before adding them to your combo.
Unproven supplements are backed by tradition or by mechanistic, animal, epidemiological, or anecdotal evidence, but not yet by convincing human trials. At this point, they are not good candidates for your combo.
Inadvisable supplements are either potentially dangerous or simply ineffective, marketing claims notwithstanding. Do not add them to your combo. At best, they’ll be a waste of money; at worst, they can cause you harm.
Now that you’ve learned of various supplements worthy of your consideration, you’ll learn to integrate them into synergistic combos. You’ll discover a core combo (composed of the most important and least controversial supplements) and several specialized combos. Each specialized combo is optimized for a specific population. The simplest way to formulate your own combo is to combine the core combo with the specialized combo that best fits your situation, needs, and primary health goal.
Then comes the FAQ, in which we cover common questions that may arise when selecting and combining supplements. With all this, you should be able to identify and assemble the supplement combo best suited to your objective.
Introduction
Any carbs you ingest, your body breaks down into glucose, also known as blood sugar (since it travels through your bloodstream). In this introduction, we’ll see how blood sugar (aka blood glucose) and insulin can be measured; but first, we’ll review some background information about glucose and its relation to diabetes mellitus (better known as simply diabetes).
Glucose is a simple sugar. More precisely, it’s a monosaccharide (mono- meaning “single” and saccharide meaning “sugar”). To store glucose molecules, your body combines them into a polysaccharide (poly- meaning “several”): glycogen.
Depiction of glycogen
Glycogen gets stored in your liver and muscles. If, through prolonged fasting or intense exercise, you deplete your glycogen stores, your body resorts to gluconeogenesis — the making (-genesis) of new (-neo-) glucose (gluco-).[1][2]
Glycogen storage and gluconeogenesis ensure that your body always has enough glucose, whereas insulin ensures that your blood never has too much. Insulin (a hormone produced in your pancreas) rises when blood glucose[9] rises; it lowers blood glucose by telling various cells to absorb it (for storage in your liver or muscles, or for immediate use) and your liver to stop producing it.[10]
The ability of cells to absorb glucose in response to insulin is called insulin sensitivity, and low insulin sensitivity is called insulin resistance — the more sensitive, the less resistant, and vice versa. It is also possible for you to produce too little insulin, if you have type 1 diabetes or are in the late stages of type 2 diabetes, in which case you suffer from insulin deficiency. In either case, glucose can’t be removed efficiently from your blood, causing hyperglycemia (overly high glucose levels).[11]
Hyperglycemia causes oxidative stress and inflammation and impairs several physiological processes,[12][13][14] thereby damaging your body and increasing the risk of many diseases — cardiovascular diseases, mostly,[15] but probably also cancer, Alzheimer’s, and Parkinson’s.[16][17][18]
Insulin resistance paves the road to type 2 diabetes, which accounts for 90% to 95% of all diabetes cases and has become a global health issue. In 2016, the World Health Organization (WHO) estimated that the percentage of diabetics in the world population had nearly doubled since the 1980s, for a total of 422 million diabetics. However, while the incidence keeps increasing in some countries, on a worldwide scale it seems to have either leveled off or decreased since the early 2000s.[19]
In 2017, the Centers for Disease Control and Prevention (CDC) reported an important, steady increase in the rate of diabetes in the US over the past 60 years, with 30.3 million Americans (nearly 1 in 10) having diabetes and 84.1 million American adults (approximately 1 in 3) having prediabetes[20] (which is to say, blood glucose levels high enough to be harmful and lead to diabetes[21]). One should note, however, than other sources have reported a decrease in the incidence of diabetes in the US since the early 2000s.[19]
Worldwide diabetes prevalence
Adapted from Cho et al. IDF Diabetes Atlas. 2017. ISBN:978-2-930229-81-2
The major cause of type 2 diabetes is excess caloric intake and the resulting obesity. Unsurprisingly, weight loss can help. One review found that weight loss from all kinds of interventions — surgery, appetite-suppressing medicines, lifestyle interventions, or a combination — alleviates diabetes.[22]
Surprisingly, many long-term studies that used only a diet to achieve weight loss reported only modest improvements in diabetes. Why? Probably because few achieved _substantial _long-term weight loss.[23] Moreover, exercise in itself can help reduce the risk and severity of type 2 diabetes.[24][25][26]
Exercising regularly and maintaining a healthy weight are the two major pillars of metabolic health, but insulin resistance can be complex, both mechanistically and causally. As a result, the basics may not always cut it, and what’s effective for one individual may not be for another. Unfortunately, researchers are often unable to explore interindividual differences, leaving diabetics to fight their disease through trial and error, based on what’s effective for a majority.