I am a registered dietitian and I often have patients who are interested in trying the ketogenic diet or trying a plant-based diet plan. The people I counsel want to know which is healthier, which is more sustainable, and of course, which will lead to effective weight loss. There's no easy answer, but I can provide some advice.
Long-term data on the ketogenic diet for weight loss is lacking. Though, we do have plenty of evidence that a plant-based diet can lead to weight loss, and a longer life. A 2014 study found that individuals on a strict plant-based diet were more successful at dropping pounds when compared to other popular diets. Further, a 2019 study found that when meat protein was replaced with plant protein, the risk of heart disease went down.
So what if you took out the bacon, burgers and butter? Could you still reach that coveted ketogenic state? The answer is yes.
The science behind ketosis
Your body’s preferred fuel is glucose. Your muscles and brain love it so much that they will seek it out above all other food sources. Therefore, when you take the glucose source away by cutting carbohydrates, the body will revolt (the keto flu) and then seek other alternatives.
When protein is not prevalent, the body can’t turn it into glucose. Even if it could, it’s not enough for the brain. Therefore, the body seeks out its last macronutrient left: fat. It takes the body around three or four days to burn fat as fuel — and when it does, it produces ketones, which ultimately supplies the brain and the rest of the body with the energy they need. Ketosis is considered a natural metabolic state.
The long-term impact of a meat-heavy keto approach is unknown
There are numerous studies showing the positive impact of low-carb diets, but few examine the long-term impact of a meat-heavy approach as seen in the ketogenic diet. Until more research is provided, there may be some compelling reasons to rethink animals as the primary source of food.
For starters, much of the meat prevalent in keto cookbooks include processed options like bacon and sausage. A recent study showed that even small amounts of red and processed meats may increase the risk for early death. Another reason to reconsider a meat-heavy keto approach is the impact it may have on the microbiome. While plants high in fiber, prebiotics and probiotics can help good bacteria flourish, red meat, fried foods and high-fat dairy may quickly increase the bad bacteria.
But a traditional keto diet may be beneficial to the gut microbiome in some ways, according to a recent small study published the May 2020 issue of Cell. Researchers tracked microbial shifts related to the diets of 17 overweight or obese men for a period of two months, with additional follow-up research on mice. Their findings suggested that the keto diet has potential anti-inflammatory effects on the gut microbiome — in both humans and mice.
Another study, published in January 2020 in Nature Metabolism, examined the effects of a keto diet on immune cells in mice. The results suggested that the keto diet may help lower inflammation and improve metabolism, as well as reduce the risk of diabetes. However, these potential benefits were only present in the mice for a short period, according to researchers, which suggests that following the keto diet over limited periods of time may be necessary to reap such benefits from it.
How to achieve plant-based ketosis
Plants are typically a source of nourishment on the ketogenic diet, but they often don’t comprise the fat portion of it. Instead, they act as the delivery system for vitamins, minerals and fiber. Broccoli, spinach, kale and cauliflower are all examples of nutrient-dense, non-starchy vegetables that fit in well on the keto diet.
However, finding plants that provide more protein and less carbohydrates is where the challenge begins. Seeds (such as hemp seed) and nuts (such as almonds) provide small amounts of protein, but for more robust protein content, consider small amounts of soy, in the form of organic, non-GMO tofu or tempeh. Further, if the plan is to only eliminate meat coming from four-legged animals, then eggs, fish and even dairy can be added into a plant-based (not vegan) approach.
Fats can be added easily and may include:
- Nuts (such as macadamia nuts)
- Avocado, olives, coconut (and their oils)
- Unsweetened nut butters
- Seeds (such as hemp, flax and chia)
- Flours (such as coconut or almond flours)
Here are some options that may work on a plant-based ketogenic diet.
A day on the plant-based ketogenic diet can vary, but typically, its broken down into 5% allocated to carbohydrates, 30% allocated to protein and 65% or more allocated to fat. “V” indicates a vegan dish or snack.
- Coffee with keto creamer
- Sautéed extra firm tofu cubes with curry powder, salt and pepper, topped with avocado slices in a low-carb wrap (v)
- Eggs mixed with sautéed onions and mushrooms and cooked in muffin pan
- Keto pancakes (there are several mixes available online) topped with coconut butter and cinnamon (v)
- Vegetable frittata muffins (v)
- Roasted cauliflower and tempeh with pine nuts, served on top of broccoli rice sautéed in coconut oil (v)
- Hard-boiled egg with low-carb seed and nut crackers
- Plant-based chocolate protein shake made with vegan protein powder, pure cocoa, unsweetened almond milk and avocado (v)
- Roasted Brussels sprouts topped with almonds and tahini (v)
- Baked eggs in tomato sauce
- Shirataki noodles, cooked and sautéed with asparagus, garlic and olive oil (v)
- Broccoli topped with vegan spinach pesto and a low-carb veggie burger (v)
- Tempeh burger in cauliflower bun with a side salad (v)
- Arugula salad with lemon juice and olive oil with seared extra firm tofu (v)
- Seared salmon with zucchini fries (cuts zucchini into sticks, top with extra virgin olive oil, salt and pepper and roast in oven)
- Almond butter bites (made by mixing nut butter with hemp seed, almond or coconut flour, sea salt) (v)
- Keto rolls with vegan cheese (v)
- Handful of macadamia nuts (v)
- Seaweed snack strips (v)
- Tofu jerky (v)
- Salmon jerky
- Plain coconut yogurt with chopped nuts (v)
- Cashew butter in celery stalks (v)
- Guacamole and red pepper sticks (v)
- Keto peanut butter bread (v)
- Unsweetened coconut strips (v)
A plant-based ketogenic approach is possible and can be the perfect solution when seeking out both quantity (fat) and quality. It may take more effort to find high-fat, moderate protein plant sources but the payback, years later, may be worth it.
Editor's note: This story was updated on September 21, 2020, to include findings from recent studies.