Type 2 diabetes is by far the most common form of diabetes (around 90% of all cases).1
The disease is getting more and more common, and there’re already an estimated 330-500 million people with type 2 diabetes worldwide.2
Most, but not all, people who are affected are overweight (especially those carrying excess abdominal fat), are middle aged or older, and may have high blood pressure, low HDL and high triglycerides.3 Although there is a growing trend of younger people, even teenagers, developing type 2 diabetes.4
For more on the background to the epidemic, how you can test if you have diabetes and how to naturally regulate your blood sugar, please read our evidence-based guide:
Type 2 diabetes results when the body can no longer handle large amounts of circulating blood sugar.5 As the blood sugar increases, the body needs to produce larger amounts of the blood sugar-lowering hormone insulin. However, over time sensitivity to insulin can decrease and the blood sugar rises out of control. At the time of diagnosis, people with type 2 diabetes often have ten times more insulin in their bodies than what’s normal.6 As a side effect all this insulin can lead to fat storage and weight gain, something that often has been going on for many years before the disease is diagnosed.7
So what’s the cause of this? This is still controversial and much debated. But there appears to be a clear correlation with the amount of sugar in the food. The more sugar people consume the more they get diabetes in the long run. According to a recent investigation this correlation is found in all countries around the world.8
Probably also contributing is ingestion of other rapidly-digested carbohydrates, such as white bread and pasta, because these too cause a rapid rise in blood sugar.9 Here too there are clear linkages: people who eat more simple carbohydrates are more likely to get type 2 diabetes.10
The associations between sugar, rapidly-digested carbohydrates and type 2 diabetes hold even in more rigorous studies. To give advice in favor of carbohydrate-rich food increases the risk of getting type 2 diabetes and worsens blood sugar levels in people who already have type 2 diabetes.11
Type 2 diabetes could thus very well be called sugar disease. And since starch in bread turns into glucose in the body – white flour is in fact also a form of sugar.12
Treatment of type 2 diabetes
How do we treat type 2 diabetes? Old wisdom and new science produce the same logical answer. The most important thing is to avoid eating too much blood sugar-raising food.13
NOTE: If you’re being treated with insulin, insulin-releasing tablets (Sulfonylureas) or other blood sugar medications, you may need to taper off your medications if you are eating fewer carbohydrates. Please do not attempt to do this on your own. Discuss this with your doctor before changing your diet as you may be at risk for dangerously low blood sugar levels. If you do experience low sugar levels, make sure to eat something sugary right away and contact your doctor immediately.
Other lifestyle modifications
Although other lifestyle habits can help treat type 2 diabetes, eating significantly fewer carbohydrates is definitely the most important thing.17
We recommend that initially you put all of your self-discipline into changing your eating habits. It’s hardest in the beginning (first weeks and months), and likely gets easier over time.
Gradually, as your new eating habits start to flow easier you can start trying other beneficial lifestyle changes such as:
According to recent studies there is one supplement that can help many with type 2 diabetes a little: Vitamin D. Many people are deficient in Vitamin D, especially during the winter months. 18 Studies show that supplementation can improve blood sugar and insulin sensitivity somewhat in type 2 diabetes. In addition this may help with weight loss.19
Around 4 000 IU daily (100 µg) may be appropriate for most people with type 2 diabetes. However, this may depend on your baseline level, so ask your doctor for a simple blood test to see where you are and if vitamin D supplementation is right for you.
If diet changes and other lifestyle changes don’t improve blood sugar sufficiently, then you doctor may suggest stating medications. Although medications have a role, it is interesting to note that studies have shown worse outcomes with more aggressive medical therapy.20 So far, this has not been shown with lifestyle therapy. In fact, the opposite is likely true!21
Metformin is the first-line treatment of choice. It’s an old and proven treatment that not only improves blood sugar, but it also aids in weight loss and potentially improves survival for those with type 2 diabetes.22
The most common side effects are stomach pain, nausea, or diarrhea. These usually subside with time, but your doctor may want to start at a low dose and titrate it up over time if needed.
A dose of two grams daily is often sufficient for a positive effect, and the maximum dose is three grams daily.
2. GLP-1 analogues or SGLT-2 Inhibitors?
When Metformin isn’t sufficient, or if you don’t tolerate it, then what to do? This is controversial today.
Often insulin injections are used. However, since overweight patients with type 2 diabetes already have pathologically high insulin levels, adding MORE insulin in this situation doesn’t make much sense. It will often cause a gradually worsening insulin resistance and obesity. Although not conclusive, it may even increase the risk of heart disease or death.23
Newer and potentially better alternatives are GLP-1 Agonists and SGLT-2 inhibitors.
GLP-1 agonists are injections that increase satiety, lower blood sugar and often lead to substantial weight loss (over 20 lbs is common). Together with Metformin, the effect on the majority of patients is very positive for both blood sugar and weight.
SGLT-2 inhibitors stimulate the kidneys to excrete excess glucose, thus lowering the blood glucose level without increasing circulating insulin. In fact, insulin levels tend to go down. Trials have shown reduced cardiovascular events in people with diabetes taking SGLT-2 inhibitors.24. However, they unfortunately can increase the risk of a life threatening condition called euglycemic ketoacidosis, especially in those eating ketogenic diets.25 Although this is very rare, we do not recommend SGLT-2 inhibitors for those who are eating low-carb.
Our hope, of course, is for you to take control of diabetes with low-carb nutrition so that you do not need any of these medications. Make sure you discuss your progress with your physician to see if you require medication or not.
Sometimes pills are not enough to control dangerous blood sugar levels and your doctor may recommend insulin injections. These are not without their concerns as they are expensive, may lead to weight gain, and they can also exacerbate the underlying disease by worsening hyperinsulinemia and insulin resistance.26
Fortunately, studies show that patients can quickly and dramatically reduce their need for insulin with low-carb diets.27 Therefore, if you are on insulin, please talk to your doctor before going on a low-carb diet as you will likely need to reduce your dose to prevent dangerously low blood sugar levels (hypoglycemia). Learn more in our guide Starting low carb or keto with diabetes medications.28
Can you reverse type 2 diabetes?29
Can you reverse diabetes in only six months? Without medications or surgery? Now science says you can. Two different nonrandomized trials demonstrated that low carbs diets are effective at normalizing blood sugar while also reducing the need for medications.30
No expensive injections. No surgery. Just low-carb nutrition. That’s powerful.
You can also read more blog posts about people with type 2 diabetes that have tried a low-carbohydrate diet  and inspirational stories from people who have taken control of their diabetes with low-carb nutrition.31
For example, pictured below is a large number of blood glucose readings in a person with type 2 diabetes in the first six months on an LCHF diet. The blue area corresponds to optimal blood glucose levels. Note that not one single elevated number was recorded after a few months! And then after just three days she was even able to stop daily 70E insulin injections. She also lost 68 lbs in the first year.32
Monitoring your blood sugar yourself seems to have a small positive effect, even for people with diabetes not taking insulin.33
Of course, how great the effect will be depends entirely on whether the monitoring leads to an improved lifestyle. Just checking your blood sugar and writing down the number in a book will of course not make you any healthier at all. Instead, monitoring of blood sugar can be used to help improve diet and exercise and adjust medications as needed.
We can do better
High blood sugar produces a risk for severe complications in the long run. It degrades the body’s small blood vessels, increasing the risk for heart attack, blindness, amputations and more.34
Millions of patients have suffered these complications while the medical establishment tries to “manage” the disease. Even popular press such as the New York Times promotes the concept that type 2 diabetes is a chronic progressive disease that we are failing to treat. We disagree and so should you.
It may be true that a conventional low-fat diet (today’s dietary guidelines) and medications don’t cure diabetes. But fortunately, a better treatment exists, and it’s obvious and logical when you understand.
We promote the science and practical aspects of using low carb to treat type 2 diabetes so the millions of people at risk can take charge of their own health and avoid suffering preventable complications.
The guide contains scientific references. You can find these in the notes throughout the text, and click the links to read the peer-reviewed scientific papers. When appropriate we include a grading of the strength of the evidence, with a link to our policy on this. Our evidence-based guides are updated at least once per year to reflect and reference the latest science on the topic.
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Type 1, usually diagnosed in kids, makes up the rest. However, there are two other forms of diabetes. Latent Autoimmune Diabetes of Adults LADA is a form that has been described as “halfway between type 1 and type 2.” As with type 1 you have antibodies that attack the insulin producing beta cells. LADA usually debuts later in life then type 1 and develops more slowly. Maturity onset diabetes of the young, MODY, is a rarer form that is caused by a genetic abnormality and also mimics type 1 but is diagnosed in adults.
Some disagree with the use of the word “reverse” when it comes to type 2 diabetes. The concern is that it may imply the disease is completely gone, never to return. At Diet Doctor, we use the term “reverse” to indicate that the diagnosis of diabetes is no longer present at that moment. However, we acknowledge that the diagnosis of diabetes will likely return if a patient goes back to their prior high-carb eating habits. Therefore, “reverse” does not imply a cure. Instead, it identifies a successful intervention that, if maintained, will likely keep the disease at bay.
The following study showed a ketogenic diet was effective at reversing diabetes or reducing medications in the majority of subjects.
However, more recent trials of the drug class SGLT2 inhibitors do show an improvement in cardiovascular outcomes and risk of death. One hypothesis is that these drugs lower insulin levels whereas older drugs increased insulin levels.
The studies that show no improvement with more intensive medications included insulin and medications that increased insulin. Newer drugs, like the SGLT2 inhibitors, can lower insulin and have been shown to improve risk of heart disease or overall mortality. Since lifestyle interventions, like low-carb diets and exercise, also lower both glucose and insulin, one could assume they would likewise show beneficial results although this has yet to be studied in adequately designed long-term trials.
The following trial, called the LOOK AHEAD trial, is frequently cited as evidence that lifestyle interventions do not improve clinical outcomes in patients with diabetes. However, the intervention was general calorie reduction and did not address carbohydrate intake.
With insulin-treated diabetes it’s important to monitor your blood sugar closely in the beginning when starting an LCHF diet! A diet including few carbohydrates usually causes a greatly reduced need for insulin. It’s then important to adjust (lower) the doses sufficiently to avoid blood sugar droping too low. This should always be done with support of your physician or diabetes nurse. ↩
Some disagree with the use of the word “reverse” when it comes to type 2 diabetes. The concern is that it may imply the disease is completely gone, never to return. At Diet Doctor, we use the term “reverse” to indicate that the diagnosis of diabetes is no longer present at that moment. However, we acknowledge that the diagnosis of diabetes will likely return if a patient goes back to their prior high-carb eating habits. Therefore, “reverse” does not imply a cure. Instead, it identifies a successful intervention that, if maintained, will likely keep the disease at bay. ↩
The longest published study yet on low carb for type 2 diabetes, is a non-randomized intervention trial of a 20% carbohydrate diet for people with obesity and type 2 diabetes. They published a 44-month follow-up showing continued good results on A1c, weight, and reduction of diabetes medications: