5 clinically-proven ways to lower your A1C levels naturally
Preventing, managing, and reversing type 2 diabetes often involves controlling and lowering what’s known as your A1C level—a measurement that reflects what your blood sugar levels have been, on average, over the past 2-3 months.
According to the American Diabetes Association, type 2 diabetes can be diagnosed based on a person’s A1C level. This is because your A1C levels are typically more stable and harder to change when compared to other forms of blood sugar measurements (such as continuous glucose monitors).
For this same reason, people with type 2 diabetes are often encouraged to set goals to lower their A1C levels. Doing so would indicate that they’re sustainably decreasing their blood sugar levels over time and progressing towards better outcomes (and possibly even reversing their type 2 diabetes altogether).
But, how can you reduce your A1C levels without the need to resort to pharmaceutical interventions (and the potential side effects that they bring)?
The first step is to talk with your healthcare provider.
Everyone has their own unique circumstances that may make one health solution better than another. Fortunately, research has shown that there are multiple ways to lower your A1C level, many of which do not involve medications.
Here, we’ve put together a summary of methods for lowering your A1C levels naturally, each of which is backed by clinical evidence.
TABLE OF CONTENTS
- What is your A1C (and what exactly does it measure)?
- What is a good (or “normal”) A1C level?
- What happens when your A1C is too high?
- What happens if I don’t lower my A1C?
- What can affect your A1C level?
- How quickly can you lower your A1C?
- 5 Clinically-proven ways to lower your A1C naturally and without medication
- 1. How weight loss can lower your A1C
- 2. How exercise can lower your A1C
- 3. How the right healthy eating plan can help lower your A1C
- 4. Natural supplements that can lower your A1C
- 5. Medical Probiotics
- Final Thoughts
- Additional FAQs
What is your A1C (and what exactly does it measure)?
A1C is a shorthand reference for “HbA1C,” which is a measurement that tells you what percentage of the hemoglobin within your red blood cells are coated in sugar. (Hemoglobin is the molecule that binds to oxygen during passage through your lungs and transports it to the tissues of your body. It also is what makes red blood cells red.)
Measuring your A1C levels helps you assess what your average blood sugar levels have been over the past few months1.
Blood cells typically last about 2-3 months in your bloodstream before being replaced. During this time, they will spend most of their lives zooming around the body via the bloodstream where they continuously bump into sugars that are also being transported through the bloodstream.
Sometimes, these encounters cause the sugars to get stuck to the surface of red blood cells. Scientists have found that the amount of sugar you have in your blood correlates with the percentage of hemoglobin within your blood cells that have sugar attached to them.
Put another way: the more sugar you have in your blood, the more sugar-coated hemoglobin you'll have within your blood cells.
The attachment of sugar to hemoglobin within red blood cells can happen when the cells are young or old. Because of this, measuring the percentage of hemoglobin in red blood cells that are coated in sugar can give you an idea about whether your blood sugar has been high or low for the past few months (the lifespan of the red blood cells being analyzed).
In the laboratory, when analyzing blood samples, sugar-coated hemoglobin in red blood cells gives off a signal that researchers can detect which is known as the A1C signal.
That’s why this blood test is called an A1C test.
What is a good (or “normal”) A1C level?
According to the American Diabetes Association as well as the Centers for Disease Control, people without diabetes typically have an A1C result of 5.7% or lower (meaning that 5.7% or less of their hemoglobin in red blood cells were found to be sugar-coated)2.
If your A1C levels fall between 5.7% and 6.4%, you qualify as having pre-diabetes.
A1C levels that are above 6.4% indicate that you have diabetes (reference graphic below).
What happens when your A1C is too high?
With rising A1C levels comes a greater risk for diabetes and its associated health conditions.
Even though sugar is arguably one of the most important energy sources in the body, it can also damage body tissues when there is too much of it.
An increase of just 1% in A1C levels is associated with a 15%-20% increased risk of developing heart disease18. The flipside is that a decrease of just 0.8% in A1C levels may decrease a person's odds of heart disease by as much as 45%18.
Blood vessels in the retina, as another example, can deteriorate after prolonged exposure to high levels of sugar, leading to partial vision loss.
Similarly, nerve cells throughout the body can be damaged by high blood sugar which, among other things, results in pain3.
Given the negative effects of having high A1C levels, it’s often a goal for people with type 2 diabetes to lower their A1C levels. (Exactly what you should target for your A1C levels depends on your unique circumstances; talking with your doctor can help you identify a personalized goal.)
What happens if I don’t lower my A1C?
As A1C levels are a reflection of blood sugar levels over time, having chronically high A1C levels increases your likelihood of developing cardiovascular disease, kidney disease, vision loss, and peripheral nerve damage—all of which are common in unmanaged type 2 diabetes3.
What can affect your A1C level?
A1C levels are influenced by a number of factors including your diet, physical activity levels, other unrelated health conditions, stress, sleep, medication you may be taking, and your microbiome.
Fortunately, this means A1C levels are not set in stone—if your A1C levels are high, there are multiple ways to go about lowering them.
How quickly can you lower your A1C?
Lowering your A1C levels will take time, mostly because your A1C levels represent an average measurement of blood sugar over a 2-3 month time period.
Because of this, momentary changes in blood sugar may not have a large effect on your A1C results.
However, sustained efforts that help you lower your blood sugar levels for longer periods of time—such as dietary changes, medication, or restoration of beneficial bacteria to the gut microbiome—can lead to a drop in your A1C levels that may be noticeable after just a few months.
5 Clinically-proven ways to lower your A1C naturally and without medication
For many people, lowering their A1C levels is an attainable goal but it’s not without its challenges. Changing your diet and exercise level for a sustained period of time isn’t easy, and it’s made all the more difficult when you’re unsure of which diets, which supplements, or which exercise routines are actually known to help people with diabetes.
These questions have been the focus of research for decades. Through numerous clinical trials, various methods for managing A1C levels have been put to the test and some have shown very promising results.
1. How weight loss can lower your A1C
Weight loss has been shown in numerous studies to be correlated with a decrease in A1C levels.
Too much body fat decreases the body’s ability to respond to insulin—a hormone released by the pancreas which tells body tissues to start removing sugar from the bloodstream4.
Type 2 diabetes is characterized by a partial breakdown in the body’s ability to sense and respond to insulin signaling, ultimately resulting in high blood sugar levels for extended periods of time.
This, in turn, leads to high A1C levels.
Because excess body fat appears to suppress the effect of insulin, it makes sense that reducing body weight could potentially help re-sensitize the body to insulin signaling and result in a decrease of A1C levels4.
This theory has been put to the test in clinical trials.
An analysis of more than 50 clinical trials, involving more than 17,000 total participants, found that weight loss—via bariatric surgery or intensive lifestyle intervention—led to a decrease in A1C levels.
This study went on to suggest that, based on these previous findings, people with type 2 diabetes may expect to decrease their A1C levels by ~0.1% point for every 2.2 pounds they lose (on average)5.
It’s important to note that this general statement will not be true for everyone. Some may require more weight loss to see a decrease in their A1C levels.
The authors similarly note that a reduction in A1C levels was more likely in people who initially had very high A1C levels, suggesting that as you get nearer to the diabetes threshold of 6.5%, it becomes harder to reduce your A1C levels.
Nonetheless, reducing body weight does appear to be an effective way to reduce A1C levels6.
Intensive interventions, such as healthy eating plans guided by dietitians and increased physical activity as allowed by your healthcare provider, have also proven to be effective at losing weight and decreasing A1C levels.
One of the more immediately effective methods for doing this is to undergo bariatric surgery in which the digestive tract is modified to reduce the amount of food consumed and absorbed. Bariatric surgery is expensive and is not without risks as complications can arise both during and after surgery)7. Speak with your healthcare provider to learn more about this procedure.
2. How exercise can lower your A1C
According to the American Diabetes Association, exercise is defined as any planned physical activity that increases your energy output. This can take the form of walking, running, swimming, weight lifting, or resistance training (among many, many other forms)8.
When we exercise, our muscles have to burn energy to contract. That energy enables us to propel ourselves forward or to lift heavy objects. And that energy largely comes from sugar.
Muscle cells have their own stores of sugar that they turn to in times of need. However, those stores can be depleted relatively quickly. Once that happens, they turn to the bloodstream for help.
Muscle cells can remove sugar from the bloodstream when they need it, and this helps to lower blood sugar levels.
Experts advise that people with type 2 diabetes get approximately 150 minutes of moderate to intense exercise spread out across at least three days a week in order to reduce their blood sugar levels8.
Both aerobic exercises (such as running, swimming, biking), as well as anaerobic exercises (powerlifting, isometric training, resistance training), have been shown to help reduce A1C levels.
A major challenge to this method of blood sugar management is that its benefits are short-lived—once exercise has ceased, blood sugar levels are likely to rebound.
This is likely why physical activity alone is not very effective in causing long term change to a person’s A1C levels.
3. How the right healthy eating plan can help lower your A1C
When it comes to managing type 2 diabetes, a healthy eating plan is also a major focus for intervention.
This is because blood sugar levels are heavily influenced by the foods we eat: If we eat meals that are high in sugar content, our blood sugar is likely to be higher as well.
Low calorie and low carbohydrate diets
Many studies have looked at the effect of calorie restriction on blood A1C levels. A calorie is a unit of measurement describing the amount of usable energy an item has. Our bodies can use fats and sugars as fuel.
When we need more energy than our food provides, our body will turn to its internal resources such as sugars that are in the bloodstream or stored in the liver. Reducing calorie count can, therefore, be a reasonable way to encourage your body to use it’s sugar stores and ultimately lower your blood sugar levels.
One clinical trial involving people with type 2 diabetes, known as the DIRECT study, had participants reduce their caloric intake to just 825 - 853 calories per day for three to five months, followed by gradual reintroduction of higher calorie meals.
The researchers found that this strict diet led to 46% of participants having reduced A1C levels (below 6.5%) one year after the trial started; a number which dropped to 36% at two years5.
That this intervention was effective is promising, however, the decreasing number of participants who managed to keep their A1C levels down highlights a significant problem with low-calorie diets: They’re often difficult to maintain over a long period of time.
Many studies have found that low-calorie diets, as well as carbohydrate-restricted diets, can be effective at reducing A1C levels for short periods of time but often fail to have a sustained impact7.
If you’re considering one of these diets, you should first discuss it with your healthcare provider. Studies in which calorie restriction or low-carbohydrate diets were most effective also included professional guidance.
Foods that can lower your A1C
Strict diets are difficult to adhere to, but incorporating certain foods into your diet may be easier. Clinical trials have explored the effect of specific foods on A1C levels in people with type 2 diabetes.
Primary among these are foods that are rich in soluble fibers. Fibers are carbohydrates found in plants that our bodies can’t easily digest 9.
Fibers are believed to help blood sugar levels in many ways. Because they’re hard to digest, fibers slow the digestion process and reduce the speed at which sugars enter the bloodstream, giving our body more time to handle blood sugar levels before they get too high.
Additionally, certain dietary fibers may also encourage the growth of diverse and beneficial bacteria in the gut microbiome (which can then have its own positive effects on a person’s blood sugar levels).
Large scale studies looking at the effect of dietary fibers on A1C levels have found that diets with large amounts of fiber (specifically cereal fibers) tend to cause a decrease in A1C levels of approximately 0.21%-0.5%10
Finally, it’s thought that fibers may help lower blood sugar levels by helping us feel full, so eating a high fiber diet may decrease the total amount of calories that you end up eating.
Some foods that are high in fiber include:
- Beans and legumes (black beans, kidney beans, pintos, chickpeas, white beans, and lentils)
- Fruits and vegetables
- Nuts such as walnuts, almonds, and peanuts
- Whole grain pasta, cereal, and oats
- Flax seeds
Similar to foods high in fibers, foods that are high in resistant starches—complex sugars that are difficult for the human body to break down—are thought to have a positive impact on blood sugar levels.
However, clinical trials have shown mixed results wherein some studies have found a positive impact on participant A1C levels while others have not. Further research will be needed to confirm whether resistant starches can help lower A1C levels.
4. Natural supplements that can lower your A1C
In addition to a healthy eating plan and physical activity, supplements may be helpful when lowering your A1C levels. Numerous supplements have been put to the test in clinical trials, however, few have demonstrated a consistent benefit for people with type 2 diabetes.
Here are some of the tested supplements that have overall shown a positive effect:
You may recognize fenugreek as a common ingredient in Indian cuisine. Many cultures throughout the Mediterranean, southeastern Europe, and western Asia have recognized fenugreek as having medicinal properties. When crushed, the seeds of this plant release a thick liquid composed of approximately 50% fiber.
Two clinical trials have found that fenugreek extract may help to lower A1C levels in people with type 2 diabetes.
These studies were not large, but when their data were considered together researchers concluded that fenugreek leads to about a 1% decrease in A1C levels, though this difference was marginally significant—suggesting a need for larger trials.
In addition to the high fiber content, fenugreek may have beneficial effects owing to some of the many compounds found within its seeds.
This is both interesting and causes for caution:
Researchers still need to examine how each of these compounds may affect the human body, especially when in the presence of other drugs (such as metformin)11.
Similar to fenugreek, Gymnema is a tropical plant native to southern Asia and parts of Africa. The leaves and roots of this plant have long been thought to have medicinal qualities.
One arm of modern research focuses on exploring traditional medicines from various cultures to understand if and how they are medicinal, including Gymnema.
One study specifically examined if Gymnema could be beneficial in people with type 2 diabetes. The study comprised 47 people, some of which were given 400mg of water-soluble extract 18-20 months. At the end of the study, participants receiving the extract were shown to have lower A1C levels.
This is a promising start, but additional studies will be needed to understand how this extract has its effect, and under what conditions it is most effective while still being safe11.
One plant compound that can be isolated from Oregon grape, European barberry, Phellodendron, and others is known berberine. This compound is believed to have an effect on A1C levels that is similar to metformin.
In a study involving 37 people with type 2 diabetes, researchers randomized the participants into two groups: one to receive 500mg of metformin and one to get 500mg of berberine extracts three times daily for three months.
Both groups saw a decrease in A1C levels with no significant difference between the two treatments, suggesting that berberine may be as effective.
However, this is only one trial, and multiple more are needed to determine the extent of berberine’s impact on people with type 2 diabetes11.
Milk thistle, a cousin to the daisy, is another plant with promise as a therapeutic.
Compounds from the Milk thistle have been studied as therapeutics in various conditions, including type 2 diabetes. Clinical trials with milk thistle extracts have shown that in some people, compounds from this plant may help to lower A1C levels (even more so when combined with berberine).
However, as with many other traditional medicines, the mechanism by which milk thistle may help is unknown. This is also reflective of the fact that more studies are needed to better understand the properties of this plant’s extracts11.
Aloe vera gel
Many people know Aloe vera as a treatment for sunburns. But it turns out Aloe vera may also be helpful in other contexts.
Researchers have used a specific type of Aloe vera gel (not the kind used to treat sunburns) in studies looking at prediabetes and type 2 diabetes.
After 8 weeks of treatment, they noted that A1C levels decreased significantly in those with diabetes, indicating that this may be beneficial.
Research is ongoing to study how this is accomplished and how Aloe vera gel may be effective and safely used11.
5. Medical Probiotics
Probiotics are being studied as potential therapeutics in many areas of medicine, including in the treatment of type 2 diabetes.
This is based on the fact that people with type 2 diabetes are often found to be lacking certain bacteria in their gut microbiome.
Numerous studies have explored the link between our gut microbiome and type 2 diabetes. There are many connections, but in general, it can be boiled down to having a diverse gut microbiome with certain bacteria—such as Akkermansia muciniphila—may help to reduce inflammation and regulate blood sugar levels.
There are multiple ways to encourage diverse and beneficial gut microbiome. Increasing the amount of fiber in your diet, for example, can help encourage the growth of beneficial bacteria. These bacteria are able to use fiber as a source of nutrients. When fiber is present in the diet, these bacteria will break down the fiber and, in turn, spit out butyrate—a short-chain fatty acid that can be absorbed by human cells and is known to have multiple beneficial effects on blood sugar control.
The benefits of a high-fiber eating plan can be amplified when supplements containing beneficial bacteria are also taken. This amounts to a one-two punch by sending specific species of bacteria to your guy while also including a nutrient source—fiber—to help them grow.
One specific type of probiotic with promising potential is known as a medical probiotic. A medical probiotic is a probiotic designed to target symptoms of a specific disease, has been rigorously characterized, and has clinical evidence of efficacy.
To date, there is only one probiotic that is classified as a medical probiotic and has been shown in a clinical trial to help lower A1C levels in people with type 2 diabetes taking metformin: Pendulum Glucose Control.
This probiotic contains bacteria that are known to frequently be absent or reduced in people with type 2 diabetes.
When administered for 12 weeks, it was found that this probiotic helped people lower their A1C levels by 0.6% relative to placebo12.
Lowering your A1C levels is a key part of managing and potentially reversing type 2 diabetes.
But changing your A1C levels isn’t an easy or quick thing to accomplish, it often requires deliberate actions and a change in lifestyle—be it a change in diet to reducing your portion sizes, a change in an exercise routine to increase aerobic exercise or the inclusion of a medical probiotic in your daily routine.
While it may take time, lowering your A1C levels is doable, it just takes a little help.
Can Apple cider vinegar lower A1C?
Apple cider vinegar is often discussed as a potentially helpful substance when treating many conditions, including type 2 diabetes.
Researchers have found that Apple cider vinegar may have some merit to it, showing in some trials that it does lower A1C levels.
However, results have been inconsistent and sparse. There may be some benefit to apple cider vinegar, but scientists have yet to hone in on the correct dosing and context in which it can be most helpful13.
Can cinnamon lower A1C?
Cinnamon has shown mixed results in clinical trials.
Some trials have shown that cinnamon extracts can help lower A1C levels, while others have not.
Taken together, this suggests that cinnamon likely has beneficial properties, but only when provided in certain contexts.
Unfortunately, scientists haven’t figured out exactly which contexts, which means for the time being it’s probably safe to assume that cinnamon shouldn’t be counted on to lower your A1C levels11.
Does alcohol affect A1C?
Alcohol consumption has been studied closely with respect to type 2 diabetes. Interestingly, it’s been found that moderate alcohol consumption has a protective effect on type 2 diabetes risk, including the lowering of A1C levels.
However, this is a risky approach to managing type 2 diabetes because high levels of alcohol consumption are known risk factors for several other related conditions and may be counterproductive.
Alcohols are also often mixed with sugary drinks which can similarly be counterproductive. It is advised that alcohol consumption be done only in moderation14.
Does oatmeal lower A1C?
Multiple studies have shown that consuming oats can be beneficial for people with type 2 diabetes.
This is likely due to the fact that oats are rich with fibers and oatmeal can be a good way to mix fiber into your diet. Among the benefits of increased oat consumption is a lowering of A1C levels15.
What is the best exercise to lower A1C?
The best exercise to lower A1C levels depends largely on your current circumstances. There is no one exercise or exercise routine that will be effective for everyone—it depends on your current activity level, your physical ability to exercise, and your history of exercise among other factors.
However, a mixture of aerobic and anaerobic exercise is the general advice for people with type 2 diabetes, specifically when done for ~150 minutes a week and spread out over at least 3 days8.
Does A1C increase with age?
The effect of age on A1C levels is not fully understood yet.
It appears that there may be a correlation between age and A1C levels, however, this may just reflect that when people are diagnosed with diabetes at an older age, they’ve often spent more time without managed care16. As we age, our gut microbiome can change, though, which could impact our A1C levels.
Will metformin lower A1C?
Metformin is first-line therapy for type 2 diabetes, meaning it’s usually the first treatment to be prescribed when medication is needed. Metformin is known to help lower A1C levels in most people17.
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