No matter what your diet has been before now, keto will be a big change. If you're coming from a standard American diet (SAD), your carbs will go way down, your protein may either go up or down, and your fat will go way up. If you're coming from a bodybuilding-style diet, your fat intake will jump to alarming levels, and your protein will likely drop significantly.
'Cutting out carbs without advice can be dangerous, and can put you at risk of deficiencies in the long-term,' warns Dr Barclay. 'If you're looking to lose weight, burning fat may sound like the key to success, but in actual fact it comes with some risks, and may not be effective in the long term. The ketogenic diet is a short-term solution to a long-term health problem.'
A ketogenic diet plan is not a "special diet" that requires special foods. There is no need to buy any "low carb" packaged foods. Ketogenic foods are essentially just real, whole foods which are close to their natural state. In other words, they are not highly processed. The only exception to this is the category of artificial sweeteners. These are highly processed. However, I think these are important to include in a low carb diet plan, because a small amount of fake sweetener has less of a negative effect on health than the standard amounts of sugar in sweetened foods. Some people may prefer more natural sugar alcohol sweeteners, but studies have shown these are "antiketogenic" and can derail the process of ketosis for some. They effect each person differently, so you'll have to test to see if they effect your health or weight loss goals.
Note: Are you a vegetarian or vegan and want to go on a ketogenic diet? It’s still possible! Just keep in mind that the dietary restrictions can sometimes be a little bit intense. Make sure to plan ahead and prepare to aid your success. To help out, we’ve published articles (with 7 day meal plans included) for both the vegetarian ketogenic diet and the vegan ketogenic diet.