What is it?
Diabetes type 1 or T1D is the autoimmune type of diabetes that involves the destruction of the insulin producing cells of the pancreas. It used to be called IDDM or insulin dependent diabetes mellitus, because people with it need to inject insulin to make up for the fact they cannot produce their own supply. Type 1 diabetes virtually always begins in childhood.
There is nowadays recognition of a diabetes type 1.5 called LADA or latent autoimmune diabetes of adults. This has onset in adulthood, but features the same destruction of the insulin producing beta cells in the pancreas.
In type 1 diabetes the pancreatic beta cells are destroyed over a period of time by attack from our immune systems T-cells. When 80-90% of the cells are destroyed, our blood sugar control fails and insulin is required to be injected after meals to ensure that blood sugar levels remain sufficiently low to prevent damage.
The first indication that this critical threshold of cell destruction has been crossed, is when diabetics urinate a lot (polyuria), become excessively thirsty (polydipsia), and hungry (polyphagia).
People with type 1 diabetes currently lose between 10-13 years off their expected lifespan (figures from USA). They also have a much reduced quality of life. However this has not been helped by the quality of information about managing their condition that has been forthcoming from the health authorities.
There are a number of examples of people living healthily into their 90s who have been on diets that do not raise their blood sugar levels (1).
The most common age to be diagnosed with T1D is between 10-14 years.
The number of people with T1D is often put at about 10% of the total of people with diabetes. In the UK the percentage of people with the most common form of diabetes - type 2, is above 6% according to the diabetes charity, DiabetesUK (2). That would put the cases of T1D at around 0.6% of the population, although most reports I’ve seen place the prevalence of T1D far lower than this.
Maps of the prevalence of T1D indicate increasing rates the further away from the equator you get, suggesting a role for vitamin D (sunshine exposure) in reducing risk.
There are a number of factors that are now recognized to increase the risk of T1D. They are:
- Inadequate breastfeeding. Absence or inadequate breastfeeding during 1st year of life.(3). Proteins in infant formula called BSA and beta casein, are similar to membrane proteins present on pancreatic beta cells. These proteins would be broken down in an adult gut and not absorbed, but babies guts are more permeable. When these proteins are absorbed by a baby from infant formula, their immune system produces antibodies to them. As BSA and beta casein resemble proteins already present on pancreatic beta cells the antibodies they generate are also able to attack beta cells. Many studies confirm the link, and children who are exclusively breastfed have the lowest rates of T1D.
- Coxsackie type B viruses. These viruses attack the intestines and a few of them can cause type 1 diabetes, especially late onset diabetes type 1.5. The ones that are implicated in T1D are group B Coxsackie viruses, types 1 and 4 (CVB1 and CVB4). A vaccine similar to the polio vaccine may be possible preventative solution for the future.
- Mumps and rubella viruses have also been linked with T1D (4).
- Bacterial toxins? Some soil bacteria called streptomyces produce toxins that have provoked T1D in mice. It has been speculated that the presence of such bacteria in tuberous vegetables such as potatoes could cause T1D in humans. The evidence for this is weak in my view, as it does not explain differences in T1D rates seen between countries (4).
- Genetics. There is a strong genetic component to T1D with relative risk being 25 times higher than normal if you carry certain HLA genes (DR3/DR4) found on chromosome 6.
Small amounts of the hormone, amylin are normally secreted from the pancreas along with insulin. Amylin works by slowing down the rate at which food leaves the stomach, just as fats do and also by blocking glucagon secretion. As glucagon stimulates glucose release from the liver this is helpful after a meal.
However in diabetics there is a formation of toxic amylin clumps in the pancreas. The researches (and headlines) reported that this was a root cause for T1D, however I suspect like so many other recent scientific reports on T1D, they are jumping the gun. The cause of clumping is not yet established.
There is an increasing awareness nowadays that risk of type 1 and type 1.5 diabetes can be assessed via the presence of certain antibodies. These antibodies to GAD - glutamic acid decarboxylase, predict risk of diabetes a number of years before it develops.
GAD is an enzyme that converts the amino acid, glutamic acid into a calming neurotransmitter called GABA. It is found in our nervous system (hence its calming effect) and also in our pancreas. In our pancreas GABA is stored in the beta cells that produce insulin.
Now in type 1 diabetes there is an attack on our pancreatic beta cells, which produce insulin, by antibodies to GAD and antibodies to a number of other proteins in our pancreas (5). This attack will slowly destroy the pancreatic tissue, taking typically a number of years, especially with the adult onset disease.
Measuring levels of GAD antibodies can give a moderate indication of risk of developing disease (6). GAD antibodies by themselves are not an absolute indication. However the test can be combined with tests for other antibodies found in pancreatic beta cells such as:
- insulin autoantibodies – IAA,
- islet antigen 2 – IA2,
- islet cell autoantigen – ICA69
- zinc transporter 8 autoantigen – ZnT8.
If you can find 3 of these autoantibodies present then it appears that your risk of developing type 1 or 1.5 diabetes in the next 5 years lies somewhere between 50-100%. It is very likely that the risk of developing the disease is dependent upon the lifestyle of the person exhibiting these antibodies. My current belief is that if you are eating a diet low in processed carbohydrate foods and taking reasonable amounts of exercise that your risk of developing type 1/1.5 diabetes is probably going to be on the lower side.
In the UK testing GAD autoantibodies is available from Oxford University hospitals (7).
Prevention and cure
Diabetes type 1 is definitely avoidable for most people. Those who know they carry HLA genes DR3/DR4 are at increased risk and should follow the advice below.
A cure is not currently possible for most people with fully developed type 1 or type 1.5 diabetes. However, at early stages before diagnosis the autoimmune attack on pancreatic tissues can very likely be arrested before disease causing levels of damage are reached. To arrest the disease causing process any general approaches that are designed to stop the autoimmune attack on our pancreas should help.
General approach to prevention
While these general approaches are aimed at prevention, they will all likely help someone who has T1D already.
- Digestive tract integrity. Reduce the amount of gluten containing foods in your diet and replace with fermentable fibres, the sort of foods that feed the good bacteria in your gut. These are: potato, swede, turnip, squash, parsnip, beetroot and celeriac. There are many ways of preparing and cooking these. Do bear in mind that some of these foods may have a blood sugar raising effect and so only use them if you can keep your blood sugars within acceptable ranges.
- Adequate exercise. Avoid sitting for too long and punctuate any sitting you do every 30-40 minutes with standing and walking about. Walking and some short duration high intensity exercises when you are ready.
- Sleep. For most people and especially those struggling with stress and with an autoimmune disease, e.g. type 1 diabetes, 7-8 hours sleep should be a minimum requirement.
- Nutrient adequacy. Getting enough of the right vitamins and minerals is important to enable the body to work effectively. With an autoimmune disease such as type 1 diabetes this means vitamin D among others.
- Stress management. Stress management is all important for people with any medical condition. Your ability to produce stress related hormones: cortisol, adrenaline, melatonin, dopamine and serotonin at the right time, and in the correct amounts is vital for healthy sleep patterns, calmness and energy levels.
- Toxins. Whether from infection or chemicals from the environment there is no doubt that any illness and such toxins as mercury (from fillings or seafood), plastics from household items and heavy metals from exhausts all impact the severity of autoimmune diseases such as diabetes type 1.
The approaches below should help diabetics cope with their disease as well as reduce risk of developing it.
- Vitamin D. There are at least three pieces of evidence linking vitamin D levels with risk of type 1 diabetes (T1D). The first is that in sunnier countries there is less T1D. The second is that experiments with infants receiving vitamin D supplementation have shown a dose dependent relationship between vitamin D intake and risk of T1D. Finally it is an established fact that on average people with T1D have lower levels of vitamin D in their bloodstream than controls (8). It is clearly a good idea to get out in the sun and in winter in Northern latitudes to take a vitamin D supplement. Get your vitamin D levels checked out, if they are below 50nmol/L then supplementation with high dose vitamin D is indicated. With levels less than 100nmol/l then make sure you are consuming eggs, liver or oily fish 2-3 times per week.
- Low GI diet. The best way to control diabetes and its potential complications is to eat foods that do not raise your blood sugar levels too much. Activity levels, especially physical exercise lower blood glucose and allow some leeway in how much carbohydrate containing foods you can eat without reaching high blood sugar levels. There is a lot of advice out there, but the best way to control your levels is to use a glucometer. This allows you to measure your blood sugar levels after meals to determine just how high your blood sugar levels peak. Your own body is unique, and so you may find your results point you towards or away from foods that are not normally identified as critical for diabetic success.
- Choline. There is some evidence that low choline status may be a risk factor for T1D. If so then foods such as egg, liver, kidneys, most meat and fish are all great sources. To a much lesser extent greens such as sprouts, broccoli and chard can provide some.
- Normal protein diet. A low protein diet has been considered by some a way of reducing the dangers of kidney damage. However the evidence for this is not strong. I recommend continuing with normal amounts of protein in your diet even if you do have diabetic nephropathy (9).
- Stress reduction. This can't be emphasized too much. All the stress hormones impact on blood sugar, and so you may be following the right diet, but if your sleep, exercise and relaxation patterns are not right you will struggle to get the best possible blood sugar control.
Treatment for T1D is based around the administration of insulin by injection or continuous infusion to keep blood levels of sugar and ketones low.
The major issue is to judge the optimal level of insulin to use. This is no easy matter. The standard treatment protocol is three times better than the intensive protocol at avoiding hypoglycaemic episodes, where a patient’s blood sugar drops too low. The flip side is that the intensive regime avoids the long term complications of the disease a lot better.
Nowadays there are devices that have slightly improved the downsides of intensive therapy by continuous monitoring of blood glucose levels and release of insulin based on these readings. The pumps are considered to improve quality of life a well as life expectancy, by improving glycaemic control.
2) http://www.diabetes.co.uk/diabetes-prevalence.html Diabetes prevalence
3) http://www.ncbi.nlm.nih.gov/pubmed/22946851 Lack of breastfeeding risk for type 1.
4) https://www.idf.org/sites/default/files/attachments/article_186_en.pdf mumps and rubella
5) http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3405822/ Islet auto antigens.
7) http://www.ouh.nhs.uk/immunology/diagnostic-tests/default.aspx Autoantibody tests in UK
8) http://www.drbriffa.com/2008/03/14/does-vitamin-d-help-protect-against-type-1-diabetes/ vitamin D with scientific ref included.
9) http://www.ncbi.nlm.nih.gov/pubmed/16198932 low protein diet.