As it turns out, almonds aren’t the only superstar nuts around. Studies have shown pistachios aren’t bad to snack on either. UCLA Center for Human Nutrition researchers divided study participants into two groups, each of which were fed a nearly identical low-cal diet for three months. One group was given 220-calories of pretzels as an afternoon snack, while the other sect munched on 240-calories worth of pistachios. About a month into the study, the pistachio group had reduced their BMI by a point and improved their cholesterol and triglyceride levels, while the pretzel-eaters stayed the same.
In September 2018, researchers at Harokopio University in Athens released a study that suggests adhering to the Mediterranean diet can promote better sleep, specifically in older adults. While more research needs to be conducted to determine exactly how and why the Mediterranean diet improves sleep quality, senior study author Dr Mary Yannokoulia suggested that the connection could have to do with the presence of the sleep-promoting hormone melatonin in foods like olive oil, fish and fruit.
Really, it shouldn’t be so difficult to figure out which eating regimen will set fire to fat while maintaining muscle. Fortunately, the International Society of Sports Nutrition just released its position paper, which combs through all existing scientific studies to report how every diet will affect your body composition. Here, we’ve pulled five of the most six-pack-friendly diets and streamlined how they’re great, as well as why they might be right (or wrong) for you—according to the hard science.
The DASH diet, the Dietary Approaches to Stop Hypertension diet, is mainly used to lower blood pressure and cholesterol, but it may also help you to lose weight. This diet emphasizes the consumption of foods that are low in cholesterol and saturated fat. It encourages eating a lot of fruit, vegetables, whole grains, and low-fat dairy foods. If you are looking to lose weight with the DASH diet, all you need to do is understand how the diet is structured and modify the diet to suit your weight loss needs. You will start seeing results in a few weeks to months’ time.
The remaining calories in the keto diet come from protein — about 1 gram (g) per kilogram of body weight, so a 140-pound woman would need about 64 g of protein total. As for carbs: “Every body is different, but most people maintain ketosis with between 20 and 50 g of net carbs per day,” says Mattinson. Total carbohydrates minus fiber equals net carbs, she explains.
What the diet guru says: According to David Zinczenko, author of The 8-hour Diet, eating all your meals within a set window is the key to burning fat. ‘By carving out an eight-hour window in which to eat to your heart's content, you'll burn your body's fat stores effortlessly. The science is actually simple: for several years, researchers have been producing remarkable weight loss results in people using "intermittent fasting". In this case, fasting is about eating whatever you want, but staying within a sensible eight-hour window. This gives your body the chance to burn away your fat stores for the energy it needs.’
Prior to the advent of exogenous insulin for the treatment of diabetes mellitus in the 1920's, the mainstay of therapy was dietary modification. Diet recommendations in that era were aimed at controlling glycemia (actually, glycosuria) and were dramatically different from current low-fat, high-carbohydrate dietary recommendations for patients with diabetes [1,2]. For example, the Dr. Elliot Joslin Diabetic Diet in 1923 consisted of "meats, poultry, game, fish, clear soups, gelatin, eggs, butter, olive oil, coffee, tea" and contained approximately 5% of energy from carbohydrates, 20% from protein, and 75% from fat . A similar diet was advocated by Dr. Frederick Allen of the same era .
Still, the headlines keep coming. Men’s Health declared, “Ketogenic Diet Side Effects: How the Trendy Low-Carb Diet Can Give You Acne.” The health and fitness website Livestrong.com warned about “The Ketogenic Diet and Insomnia.” Other articles raised fears of bloat and constipation or cautioned that the regimen requires inhuman willpower from its followers.
The fact is, the stress that you will bring on yourself from constantly restricting every single thing you put in your mouth is far more detrimental to your health. Remember, moderation is the key! You can count your carbohydrates and follow a sensible low carbohydrate diet to control your blood glucose and your weight. Exercise will always be the key component to add that contributes to added weight loss.
On keto, I’ve adjusted my basal rates and I barely need to bolus at all. My blood glucose numbers have definitely improved and what I find really extraordinary is that I’m needing about 60% less total daily insulin, than I did before starting keto. What’s even more fascinating to me is seeing a steady straight line across my pump for 6, 12, and even 24 hours – no crazy spikes or dips in my blood sugar.
This book has helped me tremendously! My doctor recommended the Dash Diet for my high blood pressure. I have to say, it was not easy to break my addiction to sugar. Phase one (2 weeks) is painful. I failed a few times before finally breaking through and sticking with it. I had SO much success on phase one, I was afraid to move on and reintroduce fruit and whole grains to my diet so I remained on it for another 2 weeks. In one month of following the diet closely I lost almost 20 pounds. My blood pressure dropped so dramatically that my medication had to be significantly decreased. I did not do the exercise as recommended in the book due to very low energy levels, but imagine that if I had, I would have lost more weight. I highly recommend this book to anyone who has high blood pressure or cholesterol and wants to lose weight.
In the 21 subjects the successfully completed the study, scientists observed a 16% decrease in Hemoglobin Ac from baseline to week 16.  Subjects experienced an average decrease in body weight of 8.7 kg (19.2 lbs.).  Additionally, their average blood glucose levels decreased a total of 16.6% and their average triglyceride levels decreased 41.6%. 
What the diet advocate says: 'The key components of a Mediterranean diet are lots of vegetables, olive oil, oily fish and nuts, with no calorie restrictions. Combine that with cutting down on sugar, which was traditionally a rarity in the region, and you’ve got the base of the Mediterranean diet right. And if you get the base right you can eat a little of whatever else you like,' says Consultant Cardiologist Dr Aseem Malhotra.
When you eat foods high in carbohydrates and fat, your body naturally produces glucose. Carbohydrates are the easiest thing for the body to process, and therefore it will use them first – resulting in the excess fats to be stored immediately. In turn, this causes weight gain and health problems that are associated with high fat, high carbohydrate diets (NOT keto).
Anna Taylor, RD, CDE, a licensed dietitian at the Cleveland Clinic in Ohio, says very-low-carb diets can hurt people with type 2 diabetes if done incorrectly. She and Keratsky say it’s important that anyone with diabetes who wants to try a low-carb or ultra-low-carb diet meet with a dietitian or physician to create a plan and make sure their eating style won’t react negatively with their current medicines.
Dairy products contain varying amounts of lactose (milk sugar), which slows down weight loss. What’s more, part of the protein in milk generates a significant insulin response, which can have the same effect. Consequently, cutting back on dairy products may accelerate weight loss. This applies especially to dairy products typically lacking in fat, such as regular milk and various yogurts, but be careful with full-fat dairy such as cream and cheese all the same. And don’t forget whey protein powder, which is pure milk protein.
There are theoretically no restrictions on where the ketogenic diet might be used, and it can cost less than modern anticonvulsants. However, fasting and dietary changes are affected by religious and cultural issues. A culture where food is often prepared by grandparents or hired help means more people must be educated about the diet. When families dine together, sharing the same meal, it can be difficult to separate the child's meal. In many countries, food labelling is not mandatory so calculating the proportions of fat, protein and carbohydrate is difficult. In some countries, it may be hard to find sugar-free forms of medicines and supplements, to purchase an accurate electronic scale, or to afford MCT oils.
Also worth noting is that low-carbohydrate, low-GI, and Mediterranean diets led to significant improvements in blood lipids with up to a 4–10% increase in HDL (4% in the Mediterranean, 5% in low-GI, and 10% in low-carbohydrate diets), 1–4% reduction in LDL (1% in low-carbohydrate, 3% in low-GI, and 4% in Mediterranean diets), and 9% reduction in triglycerides. 
Speaking of flavonoids, the waist-whittling compounds also exist in higher concentrations in red fruits such as watermelon, Pink Lady apples, and plums, meaning they also have the power to induce weight loss. In fact, a 2016 study in the journal BMJ found that people who eat a diet rich in flavonoid-heavy food tend to gain less weight, which could be promising seeing as many people tend to put on pounds as they age. In addition, anthocyanin, a specific flavonoid compound that gives red fruits their color, has been shown to reduce fat-storage genes.
I have been on a low carb diet for over 2 years. I was diagnosed a diabetic with a blood glucose over 400 mg/dl and an A1C of 12. I tried my doctors recommendations for about a year and took all the medications they told me to take. not much changed. they wanted to put me on insulin after a year. I told my doctor that I thought I could control my condition with diet and he said, “you are to far gone for that”.
I’ve been doing low-carb-high-fat (LCHF) for more than nine years. I’m not diabetic and never was so far as I know, nor was I particularly overweight. I simply became convinced over time that this way of eating is the best way to limit the damage which can be done by a lifetime of exposure to the standard American high-carb, starchy, sugary diet. I love my fatty meat, egg yolks, butter, sour cream, and more. I suppose I am fortunate I never had “carb-cravings”.
Before starting, ask yourself what is really realistic for you, Mattinson suggests. Then get your doctor’s okay. You may also work with a local registered dietitian nutritionist to limit potential nutrient deficiencies and talk about vitamin supplementation, as you won’t be eating whole grains, dairy, or fruit, and will eliminate many veggies. “A diet that eliminates entire food groups is a red flag to me. This isn’t something to take lightly or dive into headfirst with no medical supervision,” she says.