"One of the primary places where you are going to see metabolic changes on any kind of diet is in your gastrointestinal tract -- and that can include a change in bowel habits often experienced as constipation," says Sondike, who is also credited with conducting the first published, randomized clinical trial on low-carb diets. The reason, Sondike tells WebMD, is that most folks get whatever fiber they consume from high-carb foods such as bread and pasta. Cut those foods out, and your fiber intake can drop dramatically, while the risk of constipation rises.
As for if you’re dealing with health issues, you really have to defer to your doctor. For instance, if you have kidney disease, you also want to talk to your doctor about appropriate protein intake. If you have heart disease, you can still go low carb, but you may be better off opting for monounsaturated fats (avocados, nuts, and olive oil) over saturated fats (butter and red meat). Everyone’s cholesterol levels respond differently on a low-carb diet, so if yours are going up, switch to unsaturated sources of fats, Spritzler recommends. “In general, this is a diet most people can do. If you have a chronic condition, work with a doctor who understands low-carbohydrate diets to monitor you,” she adds.
If you treat your diabetes with insulin or any other medication that puts you at risk of hypos (low blood sugar levels), following a low-carb diet may increase this risk. Speak to your healthcare team about this so they can help you adjust your medications to reduce your risk of hypos. Your team may also support you to check your blood sugar levels more often.
Low-carb diets may improve high-density lipoprotein (HDL) cholesterol and triglyceride values slightly more than do moderate-carb diets. That may be due not only to how many carbs you eat but also to the quality of your other food choices. Lean protein (fish, poultry, legumes), healthy fats (monounsaturated and polyunsaturated) and unprocessed carbs — such as whole grains, legumes, vegetables, fruits and low-fat dairy products — are generally healthier choices.
Although oil or butter is high in calories, it is very slowly digested and surprisingly does not significantly increase your blood sugar. It makes vegetables taste better and can improve the absorption of certain vitamins and the essential vitamins A, D, E & K are only found in certain fats & oils. Avoid foods containing trans-fats (usually processed foods). Use oils such as olive oil, rapeseed oil or coconut oil. It also helps you feel full for longer so be more generous
However, the more weight you want to lose, or the more your health has suffered on the SAD way of eating, the fewer carbs you may want to consume at the start of the low-carb, high-fat diet. If you stay under 20 grams of carbs a day, you will be eating a very low-carb diet or ketogenic diet, in which your body converts from burning carbs (glucose) to burning fat (ketones) for fuel. Ketogenic diets can also suppress appetite, so you end up eating less without getting hungry.
There is extensive evidence for the benefit of the Mediterranean style low carb diet, including cutting your risk of heart disease and diabetes. It has even been found to reduce risk the risk of breast cancer, compared with those on a low-fat diet. Consuming extra virgin olive oil (the fresh squeezed juice of olives) seems to be particularly beneficial when it comes to cancer, perhaps because it contains compounds such as polyphenols which are known to be anti-inflammatory.
If you have type 1, it's important to know that the best way to keep your blood sugar levels steady is to carb count rather than following a particular diet. And there is no strong evidence that following a low-carb diet is safe or beneficial, which is why we don’t recommend this diet for people with type 1 diabetes. But some people with type 1 have reported needing less insulin and losing weight from following a low-carb diet.