Well, both are related to nutrition and both can be prevented or helped by the same foods and supplements.  Type 2 diabetes is normally preceded by decades of slowly increasing insulin, blood sugar, and belt-size (.. and it is always healthier to sit on your fat than have your fat sit on you).  Early prevention is very effective but there come a point when insulin production permanently breaks down.  Smart nutrition (and portion control) can first prevent overweight and diabetes, and eventually heart disease.  While, as of 2017, diabetes drugs fail.

Both conditions are epidemic with 1 in 13 Americans and 1 in 3 of those over age 60 developing 'adult' diabetes.  Most will develop heart, kidney, nerve and blood vessel diseases for an amazing 1/4th of total health care costs!  Other countries have similar increasing rates.  Later-in-life diabetes (during pregnancy being a warning) is an eventual one-way track to heart disease.

What makes a diabetic?  Simply put: when your pre-breakfast blood sugar (plasma glucose) gets over 126 mg/dL (7 mmol/L).  Another measure is when 2 hours after taking a dose of glucose the blood level is still over 200 mg/dL (11.1 mmol/L), with over 140 (7.8) starting to suggest a problem.  Pre-breakfast 95 (5.3) is good, under 36 (2) is seriously low blood sugar, while above 180 (10) a safety-valve opens that sends glucose to the urine.  To confuse anybody, the numbers changed from mg to the 18 times smaller mmole, they increase by 14% between 'blood' and 'plasma' in syringe samples -but the numbers for 'blood drop' and 'syringe-plasma' are similar.  However, it's the big picture that counts, not the decimal points of the reading.  This is one area where a blood test is important since serious organ or foot damage (!) can happen early.

In early-age 'type 1' diabetes the body stops making insulin [see: Wikipedia] needed to process sugar and starch.  Type 1 represents under 5% of total diabetes.  There is no cure and insulin, a protein, must be dosed by injection in relation to sugar and starch intake.  Type 1 can possibly be prevented with vitamin B-3 in people with declining insulin -which can show years before irreversible damage [see ENDIT or here].

In the now exploding 'type 2' diabetes, which develops in obese kids or at a more 'mature' age [Non Insulin Dependent Diabetes Mellitus, NIDDM or maturity-onset], the problem is initially not a lack of insulin but body cells became insensitive (resistant) to its effects.  Increasing amounts of insulin try to "push the gas pedal" but the system doesn't react (by taking fuel, glucose, into the cells).  In type 2, blood-sugar and (therefore) blood-insulin both become high which is a double problem.

This double problem is that:
1. High insulin changes excess blood-sugar into fat around the belly, and worse, it keeps it there.  Insulin makes and keeps you fat;
2. High blood-sugar makes blood vessels and blood components 'sticky', slowly destroying your 'arterial tree'.  Using frying temperatures when making meals makes that effect worse.

Both effects reduce blood flow to all areas of the body especially to the feet, eyes and kidneys.  Fat, around the body or as triglycerides in the blood, does nothing to promote blood circulation.  Good circulation is 50%-of-good-health.  This is why weight control, "shaking-up-the-fat" (exercise), a good multi-vitamin with minerals and extra magnesium, omega-3 [ω-3 or n-3] oils and high-fiber, low glycemic index foods are all-important.  Unhelpful are high omega-6 oils like corn, soy or sunflower while vitamin D works better than insulin drugs!  High waist size (belt length, regardless of your height) with high blood triglycerides (fats), high sugar, high insulin and high blood pressure, all lead to ill-health.  This group of symptoms is known as Syndrome X, the Metabolic Syndrome.

I remind you that this author is not a doctor and knows absolutely nothing about your specific situation.  Keeping this in mind, here are some ideas that will help you see the global picture of diabetes (kidney, leg, eye and heart disease) more clearly.

Glycemic Index (blue) of common servings: *Most fruits: 1-4 g fiber; GI: 40-60 *Beans (cup, cooked): 5-14 g 35-50 *Broad(Fava) beans (cup): 9 g 110 *Large potato with peel: 6 g; 110 *Meat, eggs, fat & most dairy: 0 g low *Most breakfast cereals: 0 g; 80-100 *Hot whole cereal: 5-10 g; 85 *Some bran cereals: 5-10 g; 40-50 *Donuts, regular breads: 0 g; 100-110

  2.  INCREASE fiber-rich vegetables and fruits that have not been processed much, beans and partially whole kernel grains (not finely ground) and omega-3 oils (flax, canola and fatty fish or fish-oil pills).  Fiber, especially soluble fiber (gel or pectin-like fiber), is truly diabetes and heart healthy as it slows and regulates the speed of the uptake of foods--which is what diabetes control is all about.  All agree about the major benefit of fiber -and it's cheaper than a glucose test strip.  Every 10 g/day increase in fiber reduces diabetes risk by up to 30%!  I'm not crazy about non-nutrient fiber, like psyllium husks a.k.a. Metamucil.

GLYCEMIC INDEX TRIAL (the high index version of the same food is in brackets) * Whole grain barley bread 58 (same, flour 100; like wheat flour bread) * Semolina [grainy durum-wheat core] pasta** 57 (durum, ground to flour 100) * Rice pre-boiled 65 (sticky rice 86) * Whole kernel barley porridge 35 (same, barley flour 98) * Whole lentils or red beans 36 (same, ground to flour 70) * Whole white or brown beans 40 (same, flour 74) Such foods were given to type 2 diabetics and despite being identical in fiber and chemical composition, the 'less ground' more intact foods reduced the amounts of glucose and insulin by 30% and a blood clot promoting factor (PAI) by 50%.  A very important study in Jan 1999 Diabetes Care.

  3.  LEARN ABOUT low glycemic index foods and glycemic load.  Not all foods release their sugars or starches at the same speed.  The slow release foods, typically the least refined foods, have demonstrated benefits.  Here is a full list of glycemic indexes.  A large portion of a high glycemic index food creates a large glycemic load.  Not good.  The graph was simplified from AJCN, Feb. 2002.  The 45 minute long blood sugar peaks, from 15-60 minutes, were totally identical, but the presence of intact whole grain structure reduced the insulin that was triggered by 50% [!].  This lingering high "white bread insulin" lowered the 1.5 to 3 hour blood sugar to below starting levels.  This causes cravings and jitters precisely because, despite of low blood-sugar, insulin prevents you from using fat reserves to satisfy such energy craving.  [And, logically, only sugar, flour, starch and maybe alcohol can fix such craving --but not fat or protein].  Remember: lingering insulin makes and keeps you fat, ratcheting fat into the cells --and then preventing its use for energy

The good news about fat is that it never raises either insulin or glucose.  This allows you to burn fat from food and from storage, if not swamped by insulin made for sugar or starch --so you lose weight.  Carbs make you make fat especially when you have high-insulin, and regardless your starting weight (AJCN, Jan. 2003).

Protein raises insulin, as shown, but while up to ½ gets used like sugar, protein doesn't raise blood glucose.  The only thing eaten here was 236 gr. (8 oz.) lean meat, providing 50 grams of protein.  Similarly, also fructose (50% of plain sugar) has little effect on glucose but it raises insulin -and cholesterol.  Notice in the last graph that type 2 diabetics have high fasting (morning) insulin.  In type 2, the challenge is to keep insulin and glucose low.  Yes, lowering carbs is safe and a valid option.

4.  DECREASE YOUR WEIGHT if it is high: obesity leads to type 2 and heart disease.  [Skinny diabetics, those not producing the fat-maker insulin, lose sugar-calories in the urine since they can't use sugar for fat or fuel.]  ALL authorities agree with weight reduction benefits in type 2, as often blood-sugar returns below the cut-off point [and technically you're cured].  As fat-cells lose fats, there are relatively more insulin receptors active per unit of cell surface and the system works better.  Moderate exercise (many benefits) and cutting down on (tasty and well-deserved) calories are ways to normalize weight.  Easier said than done.  Then there are changes in diet: try the wisdom in the books by Whitaker, Challem, Atkins and Willett (the 4 books in one frame in the links list).  None of these books has all the answers but combined they provide a wealth of information about how weight loss can be part of a pleasant life-style.  Low-carb Atkins 'still' best for weight loss. Another low carb high nutrient diet is Montignac.  Obesity is stored fat, and you'll never lose fat if you over supply with starch, carbs and refined cereals...

5.  ABOUT DRUGS... there are drugs that "raise insulin" [sic], make it work better or reduce blood-sugar by other means.  In later stages of adult-diabetes [very high blood-sugar], injected insulin [at increased levels also a poison] is often added to drugs taken by mouth.  On the surface this seems like good strategy as blood-sugar and therefore the blood marker HbA(1c) become more normal, for a while.  This marker "A-one-C" tells how many "frosted" (sugar-damaged) red blood cells you have, evidently an important thing to reduce (less than 6% is normal, 4% is good but even 7.5 may not be such a bad target).

The New England Journal of Feb. 7 2002 had a land-mark study about the superiority of non-drug approaches: "Since current methods of treating diabetes are inadequate... The hypothesis that type 2 diabetes is preventable is supported by observational studies and two clinical trials of diet, exercise, or both in persons at high risk for the disease but not by studies of drugs used to treat diabetes."

The problem with drugs is that there are effectively no studies showing they actually postpone grief and improve survival [also, 2008 analysis].  Many promising drugs and the patients on them are no longer with us.  With drugs you can 'normalize-the-numbers' to make the lab report look better but there are few studies proving that this delivers a long-term health benefit.  Diabetes drug do not fix underlying problems, have side-effects and decreasing effect with time.  Intuitively you would think that any drug that lowers blood-sugar [or cholesterol or blood pressure] should be beneficial but this is certainly not evident [UKPDS in BMJ '01-10-13: 854; changed into recommendations but further debated here].  Ask your doctor to explain this debate; it ain't easy for them either!  NEJM Sept. 9, 2004: the big new class of drugs in 20 years, with names ending with -glitazone (dangerous Avandia, problematic Actos or the withdrawn Rezulin) make you fat and promote heart failure [a 2007 editorial: 'not the answer'] and, finally, bone fractures ... while biguanide (metformin) and sulfonyl-urea (glipizide) harden the aorta while sulfonyl-urea increases deaths.