Ginger: Health Benefits, Side Effects, and How to Take It
It’s thought that people in India and China have used ginger therapeutically for at least 5,000 years, and ginger was probably used to spice up foods long before this. Over the years, interest in ginger has waxed and waned, with notable surges when Queen Elizabeth I reportedly invented the gingerbread man and now again in the 21st century as people turn to ginger shots and other spicy concoctions in the hope of garnering a range of health benefits. But is ginger a legitimate health booster, or is this all just spicy hype? Today we’ll look at what's known about the science of ginger, as well as how to best consume it.
- Ginger’s a member of a plant family that includes turmeric. Ginger is nutrient rich, and some of its phenolic compounds (e.g., gingerols) strongly influence its effects on health.
- Ginger and its metabolites accumulate in the gut, and ginger intake can improve gastrointestinal motility and reduce nausea and vomiting (e.g., in pregnancy and around surgery).
- Regular ginger intake seems to counter some sources of pain, including osteoarthritis, menstrual cramps, and migraines.
- Ginger also supports cardiometabolic health and can decrease blood pressure, improve blood sugar regulation and blood lipids, and slightly reduce bodyweight.
- Going by studies of non-human animals, ginger boosts fertility in males, increasing testosterone, sperm counts, and sperm motility. This hasn’t been well studied in humans though.
- Consuming 1 to 2 g powdered ginger per day is likely very good for you. The only thing to note is ginger can reduce platelet activity and therefore blood clotting, which is relevant if you take certain drugs (e.g., Aspirin, Warfarin).
What is ginger, and what’s in it?
Ginger’s in the same plant family as cardamom and turmeric. When we eat or drink ginger, we generally consume the rhizome, the horizontal stem from which the roots grow. The rhizome is a complex of hundreds of components, and powdered rhizome is typically 60 to 70 % carbohydrate, 3 to 8 % fibre, about 9 % protein, 3 to 6 % fatty acids, and perhaps 2 to 3 % oil that's prone to evaporating when exposed to air (it's “volatile”). Ginger’s spiciness comes mainly from gingerols, types of ketones that are thought to determine many of ginger’s effects on health. There are many other phenolic compounds in ginger (e.g., quercetin) as well as some non-phenolic ones, including terpenes, the main constituent of essential oils.
The concentrations of all these chemicals depend on factors such as where the plant is grown, how long it’s grown for, and whether the ginger is dried or otherwise processed. For example, while gingerols are the main polyphenols in fresh ginger, when ginger is dried other polyphenols named shogaols become more abundant. Likewise, ginger’s essential oils increase as the plant ages, so when oils are sought ginger is harvested later.
Does consuming ginger boost health?
There have been many experiments on how ginger or ginger extracts affect non-human animals (mice and rats, especially). While these observations are intriguing, we humans aren’t just big rodents, so today we’ll focus on carefully controlled clinical trials of ginger intake and draw on other research to speculate how ginger exerts its effects. Since ginger is probably most recommended to help with digestion, nausea, and vomiting, let’s start there.
Ginger is good for your digestive system
Multiple experiments have shown that ginger helps move food along the digestive tract by speeding how quickly the stomach empties in both healthy people and people with indigestion (“functional dyspepsia”). Going by studies of non-human animals, ginger and its metabolites then seem to accumulate in the gut. Here they probably have many actions, affecting the composition of microorganisms in the area and exerting anti-inflammatory actions that support the integrity of the intestinal barrier. As it’s clear that chronic low-grade inflammation can contribute to pain, poor cardiometabolic health, and an array of other disorders, it might be that enhanced regulation of inflammation is a common mechanism by which ginger exerts many of its positive effects. Backing this idea, regularly consuming ginger consistently reduces blood markers of inflammation (e.g., C-reactive protein) while countering oxidative stress (increasing glutathione peroxidase and lowering malondialdehyde).
Several of ginger’s constituents (e.g., 6-gingerol, 6-shogaol, and zingerone) also seem to interfere with serotonin’s ability to act on its receptors in the gut, which is intriguing because this interaction can signal to the brain via the vagus nerve that something’s up and it’s time to vomit! Sure enough, there's been lots of analysis of whether ginger intake can quell nausea and vomiting. Some of this work initially centered on seasickness, but other events that trigger the urge to be sick have since been better studied, including pregnancy, hospital operations, and chemotherapy.
By all accounts, morning sickness in pregnancy is rough, and ginger is widely touted as an antidote to it. When scientists have systematically collated all the research on ways to abate nausea and vomiting in pregnancy, ginger has shown promise, although it’s not a panacea. Many treatments can somewhat ease nausea in pregnancy, including dimenhydrinate, metoclopramide, vitamin B6, and ginger. Of these, ginger and vitamin B6 stand out though, for these two might also reduce vomiting and seem safe and well tolerated. Regarding giving birth, it’s not particularly clear whether ginger reduces nausea and vomiting during and after C section deliveries, although there are certainly hints that ginger helps a little.
Moving on to other operations, scientists have generally found that ginger slightly reduces the severity of nausea and vomiting after various operations, and once again ginger seems to fare very well compared to various herbal treatments people have tried. Ginger also seems to make chemotherapy more tolerable, for the most recent analyses reported that ginger acutely counters nausea and vomiting caused by chemo. What's more, ginger might also somewhat lift fatigue.
Ginger eases certain types of pain
Pain is notoriously poorly understood and difficult to treat, and there tends to be large variation between people in how they respond to interventions designed to alleviate pain. Nevertheless, there’s are certainly hints that ginger can reduce pain in a few conditions.
Beginning with musculoskeletal pain, oral (not topical) ginger intake reduces pain in knee osteoarthritis. This analysis of knee arthritis didn’t find that ginger improved physical function, but a previous analysis that included studies of arthritis in other parts of the body too found ginger consumption reduces disability and increases the likelihood that patients end up discontinuing arthritis treatment. Furthermore, when scientists compared various supplements for chronic musculoskeletal pain, they suggested that ginger (as a food source, not as a supplement) is among the most effective pain relievers. It’s not clear how ginger relieves this type of pain, but it’s possible that ginger inhibits the synthesis of inflammatory lipids (prostaglandins and leukotrienes), reducing blood flow and influx of immune cells to the afflicted joints.
With respect to other types of pain, several teams of scientists have explored whether ginger reduces the kind of menstrual cramps (primary dysmenorrhoea) regularly experienced by women who don’t have any apparent underlying disease. While an analysis by a notoriously stringent group of researchers (the Cochrane network) reported that there’s not convincing evidence that any supplement thwarts primary dysmenorrhoea, other scientists have concluded that consuming 0.75 to 2 g ginger powder per day in the first 3 to 4 days of the menstrual cycle mitigates discomfort. Even if there's no upside for you, I can't really see a downside in trying ginger for menstrual cramps.
Finally, when the results of 3 studies on ginger intake for migraines were compiled, ginger seemed to lower pain a couple of hours later, increasing the probability that migraines passed by this time.
Ginger supports cardiometabolic health
Even if you’re not in pain or discomfort, ginger is probably still good for you.
Starting with heart health, ginger can reduce blood pressure in the short term, provided the dose is sufficient (at least 3 g per day). Next, while the roles of blood lipids in cardiovascular health are contentious, consuming ginger might influence lipids in ways that most people consider favourable. The data on this aren’t very consistent though. In one analysis, up to 2 g ginger per day reduced triglycerides and total cholesterol. However, in a separate compilation of research on overweight and obese people, ginger didn’t affect these parameters but did raise high-density lipoprotein cholesterol. Note that while results of these two studies aren't consistent, the effects each reported would probably still please your doctor.
There are also some disparities between studies of ginger’s effects on blood sugar control. For example, whereas some work suggest that ginger doesn’t affect fasting blood sugar but does improve a proxy of longer-term blood sugar levels (HbA1c) in type-two diabetes, others have concluded that ginger does reduce fasting blood sugar while alleviating insulin resistance in overweight and obesity. Again, even if inconsistent, the changes reported in both studies are in likely beneficial directions.
Is ginger good for weight loss?
In general, ginger modestly reduces bodyweight and waist-to-hip ratio in overweight and obesity, and we know a bit about the biological bases of this. Some chemicals in ginger are structurally like capsaicin, a pungent constituent of red peppers that’s known to increase energy expenditure and hence weight loss. It does this by activating certain channels (transient receptor potential channels) located on cell membranes. Sure enough, gingerols, shogaols, and 6-paradol also target these receptors, perhaps explaining how 2 g ginger with a meal increases energy burned digesting and metabolising it. This calorie burning effect is complemented by the fact ginger can reduce hunger and subsequent food intake. While results of different studies aren’t all congruent, some scientists have also found that having 1 g ginger in the morning and afternoon respectively also boosts fat burning. Collectively it appears that ginger might slightly increase energy expenditure and fat burning while keeping hunger at bay.
Does ginger boost testosterone too?
Another reason ginger that gets lots of airtime is that some people claim it improves fertility and boosts testosterone in men. Ginger can in fact increase testosterone production in non-human male animals, particularly when the animals are exposed to conditions that increase oxidative stress. This effect might be driven by many factors, including reduced oxidative stress in the testes, improved testicular blood flow, improved blood sugar regulation, and increased production of a hormone made by the brain (luteinising hormone) that signals the testes to produce testosterone and sperm. The problem is that we just don’t know if ginger intake has these effects in humans. The only relevant “research” I’m aware of was published in an obscure journal. It documented that 3 months’ ginger intake (amount per day not disclosed) potently increased luteinising hormone, testosterone, sperm count, and sperm motility in infertile men, but the analysis is littered with flaws and weakened by missing information.
What’s the best way to consume ginger?
The fact that lots of forms of ginger have been used in studies (powdered ginger, ginger extracts, etc) has probably contributed to inconsistencies in findings of different studies. In one study, for example, dried ginger had about 5 times the phenolic contents of fresh ginger. This makes it hard to give precise dose recommendations.
Many studies have used powdered ginger, and I’m comfortable stating that a regular dose of 1 or 2 g powdered ginger per day seems to bolster many aspects of health, although the dose that reduces blood pressure might be slightly higher – perhaps 3 g per day. Because of ginger’s fiery kick, you might want to divide your daily intake into individual doses of 0.5 to 1 g, and a simple way to do this is to stir a small amount into hot water and have it as a tea. Needless to say, our favourite way to consume ginger is via gingerbread flavours of our Calm, Rebuild, or Calm & Rebuild nut butters, each of which is over 2 % powdered ginger. You can of course consume ginger in a variety of other ways too, including fresh, pickled, or crystallised, and you can also have it as a syrup, or extract.
Next, you might be wondering at what time of day it’s best to consume ginger. Ginger is metabolised very quickly, so if you’re using it for short-term effects (e.g., a migraine) then it should act quickly. Because ginger can slightly raise body temperature and energy expenditure, I tend to have it in the morning or afternoon rather than close to bedtime, but there's no convincing evidence that timing of intake really matters.
Finally, although there’s not much science on the toxicity of ginger, it appears to be very well tolerated. Perhaps the most important caveat is that high doses (5 g or more) can reduce platelet activity and hence blood clotting. This can be a good thing in some circumstances (e.g., thrombosis), but in others it can pose problems (e.g., by impairing wound healing). Related to this, ginger’s anti-inflammatory and anti-platelet actions mirror those of NSAIDs (non-steroidal anti-inflammatory drugs), such as Aspirin. This makes ginger a terrific low-risk alternative to some medications, but it also raises the possibility that ginger could be a bad option if you know you'll experience blood loss for some reason or if you take blood-thinning therapies such as Warfarin. Some research has shown that ginger doesn’t affect responses to Warfarin, but you might still want to err on the side of caution.
Spice up your life
In summary, adding a little ginger to your diet is bound to do you good. We didn’t touch on ginger’s other potential uses, which include enhancing brain health and helping prevent and treat cancer, for right now these applications are based on experiments done on non-human animals and cells, not humans. However, we did address ginger's positive effects on everything from nausea and vomiting to fat loss, and while there have been some small irregularities between studies, traditional medicinal uses of ginger have withstood scientific scrutiny impressively well.
I for one will be throwing some ginger in my next meal :-)