Last week, I wrote about the reasons for adopting a specific diet, what the foundations of a healthy nutrition are and how vegans and vegetarians can optimise their meals. In this part II, I cover the keto, carnivore and paleo diets.
A well-formulated ketogenic nutrition
Some people think that a keto diet consists of eggs, bacon and cheese. Not at all! When it is well formulated, it contains many other nutrient-rich food groups: meat (pasture-raised if possible), fish (wild-caught is better), liver and organ meats, non-starchy vegetables, dark leafy greens, mushrooms, nuts and seeds, herbs and spices, full fat dairy products, avocados, olives, coconut, some fruits, organic and locally grown if you can.
A varied and colourful diet can give you the full spectrum of vitamins and minerals needed for optimal health.
Vitamins and minerals
The most common deficiencies found in keto diets include vitamins A, B5, B7, B9, C, D and E, chromium, iodine, magnesium, selenium, as well as choline, although most of these nutrients can be obtained in sufficient quantities with the following ketogenic foods:
vitamin A: liver, fatty fish, eggs, butter, cheese, orange and yellow vegetables, broccoli, dark leafy greens
vitamin B5, B7 and B9: broccoli, cruciferous vegetables, spinach, mushrooms, almonds, sunflower seeds, meat, poultry, fish, dairy products, eggs, liver and kidney, asparagus and avocados
vitamin C: fresh lemon juice, capsicums, chili pepper, cruciferous vegetables and berries. This vitamin is extremely heat sensitive, so only very gently cook these foods or eat them raw.
vitamin D: see my blog - part I
vitamin E: sunflower seeds, nuts (almonds, hazelnuts, pine nuts, Brazil nuts), goose meat, salmon, seafood, avocados, red capsicums
choline: eggs, liver, meat, poultry, fish and dairy products
chromium: broccoli, green beans, turkey, beef, poultry and dairy products
iodine: fish, seafood, seaweed, sea vegetables, iodised salt and dairy products
selenium: Brazil nuts are one of the best sources, with only 1 to 3 nuts per day (not more due to possible toxicity).
Electrolytes
A more common issue with keto diets is an electrolyte imbalance. With lower levels of insulin and glycogen, keto beginners lose a lot of water in the first few weeks, together with essential minerals. This is why a ketogenic nutrition requires more potassium, magnesium, calcium and sodium, from the following foods:
calcium: salmon, sardines and dairy products
magnesium: unsweetened cocoa, avocados, nuts and seeds, fatty fish and leafy greens
potassium: proteins, vegetables, nuts and seeds, and avocados
sodium: 1 to 3 teaspoons of salt in addition to the sodium naturally obtained from food.
If you feel fatigued, weak, or experience cramps, twitching, numbness or headaches, among others, your electrolytes might be too low and consider supplementing, as required.
Kidney stones, food sensitivities and gout
The next possible issue is the formation of kidney stones, as many common keto-friendly foods contain oxalates (spinach, kale, cocoa, almonds, chia seeds...). See part I of this article, where I cover the topic for vegans and vegetarians.
Although keto diets generally contain much less plant-based foods than the vegan and vegetarian diets, there is still a possibility for intolerance to certain anti-nutrients and compounds found in nightshades, FODMAP foods, nuts or seeds. Refer to part I if you experience any digestive issues (gut inflammation, constipation, bloating, diarrhea...), skin or mood issues, or brain fog.
Last, people who suffer from gout shall be careful when adopting a keto diet, as the gout could flare-up during the adaptation stage, due to competitive excretion of uric and ketone acids in the kidneys.
Saturated fats and cholesterol
Many people believe that keto diets should be avoided, due to their high saturated fat and cholesterol contents. However, research has now proved - after decades of misinformation fueled by flawed studies - that these fats are perfectly fine for people leaving a healthy lifestyle.
Saturated fats and cholesterol can become an issue when they are paired with high carbs (not an issue for keto and carnivores!) or for a small minority of individuals genetically predisposed to inflammation. Then, they may contribute to increase “bad” cholesterol and the risk of cardiovascular diseases.
On the other hand, the consumption of healthy fats on a keto diet has been shown to increase the good cholesterol and to decrease the bad cholesterol and triglycerides. In the absence of high carbs and bad fat intake and other risk factors (such as smoking), dietary cholesterol and saturated fats are NOT linked to a higher risk of cardiovascular diseases. On the contrary, several meta-analysis covering millions of people across many countries found that higher saturated fat intake was associated with a decreased risk of cardiovascular disease and all-cause mortality!
In short, eating more healthy fats (from eggs, full fat dairy products, avocados, olives, coconut, nuts and seeds, good quality meat and fish) is good for you, but consuming bad fats (from processed foods, fried foods or processed vegetable oils) or excess carbs is not.
If you worry about your cholesterol levels, a blood test can reveal what your levels are. For information, the optimal ratios are TRG/HDL <2, CHOL/HDL <3.5, LDL/HDL <3... and total cholesterol levels do not reveal anything about your health.
What about carnivores?
Many opponents to carnivore diets claim that eating only animal-source foods will lead to serious nutritional deficiencies. Well, it depends. As for any other diet, a well-formulated carnivore diet with appropriate supplementation can work for some people, especially for those who cannot digest well plant-based foods or suffer from certain health issues.
Vitamins and minerals
Animal-source food is very rich in nutrients, provided that a variety of meats, fish and eggs are consumed.
Organ meats, in particular, are incredibly nutritious. They include liver, tongue, heart, kidneys, brain, sweetbreads and tripe and are particularly rich in B-vitamins, iron, magnesium, selenium, zinc, choline, as well as in vitamins A, C, D, E and K. However, they are not to everyone's taste. If you are carnivore but feel nauseous by just reading this list, you can find them in encapsulated supplements (although natural food will always be better!). Also, vitamin C might still be an issue as it is so sensitive to heat.
With regard to electrolytes, carnivores are likely to have the same issue as those on keto. See above for more details.
In short, check your blood regularly to see whether your levels of vitamins and minerals are optimal and supplement as required. Many nutrient deficiencies can take years to show up as a symptom or a disease and prevention is a much safer approach!
Can a carnivore get enough fibres?
The carnivore diet does not contain any fiber, which generally impacts the bowel function during the initial adaptation phase, as well as the balance of the gut microbiome. Starting a carnivore can lead to loose stools in some people and constipation in others.
Consider transitioning progressively, especially if you were previously eating a lot of carbohydrates from grains or vegetables. You can start by going low carb paleo or keto, before turning full carnivore, if you think it is the best option for you.
If your bowel movements haven't returned to normal after a few weeks (meaning at least once a day), or if you notice any digestive discomfort, it would be a good idea to consult a qualified health practitioner.
What about all the controversy about eating meat?
Many studies have tried to demonstrate that meat is bad for our health and the planet but they have been proven to be biased, misleading and badly conceived.
Some claim that livestock is the largest source of greenhouse gases worldwide, but the U.S. Environmental Protection Agency reports that animal agriculture contributes to 3.9% of emissions in 2016, versus 56% for electricity production and transportation, and 22% for the industry.
Other consider than killing animals to eat them is not ethical, whilst meat eaters respond that extensive plant-based agriculture kill even more animals, just of a different kind (the mammals, reptiles, birds or insects who are killed and have lost their habitat).
I don't know which way of eating is the best for the environment. However, as mentioned in part I, there is certainly a lot to do to improve on both sides, especially to avoid Concentrated Animal Feeding Operations that feed animals with GMO grains, hormones, antibiotics and worse, and to revamp extensive mono-cultures that spray pesticides, herbicides, fungicides and deplete the soils. More efforts should certainly be made to replace conventional farming by regenerative agriculture.
Certain institutions and researchers have reported that red meat consumption increase the risk of developing colon cancer or cardiovascular diseases, but the two largest observational studies on the subject (with over 1 million and 0.4 million people, respectively) have shown that unprocessed meat was not linked to an increased risk of heart disease or type 2 diabetes. So, just make sure to eat unprocessed meat and don't overcook it, as burnt, charred or fried meat might be harmful.
All this is very confusing for the general public. The best advice might be once again to do your own research, listen to both sides of the argument, try what feels right to you and monitor how your body respond.
Controversy aside, a very high protein diet can cause a few issues: it can activate what is called the "mTOR pathway", which plays an important role in regulating cell growth. Cell growth is good to build muscle mass, but excessive cell growth can result in accelerated aging and cancer proliferation. How much is too much? Hard to tell! Further research is needed to determine the protein intake that is optimal for human health, taking into consideration individual factors.
Also, when proteins represent more than 35 to 40% of total daily calories, they can overwhelm the urea cycle, leading to nausea, diarrhea or wasting, depending on genetic predisposition.
Last, as mentioned in the section on the keto diet, a small minority of carnivores might not tolerate well high levels of saturated fats and cholesterol.
Is there anything to do to optimise a paleo diet?
As mentioned in my previous blog, the paleolithic nutrition aims at mimicking the nutrition of our hunter-gatherer ancestors and includes meat, fish, eggs, vegetables, fruits, nuts, seeds, herbs and spices, if possible organic and/or pasture-raised (for animal products). It excludes grains (except wild varieties), cereals, legumes, processed foods, added sugar, soft drinks and, usually, dairy products.
The paleo diet is often described as a golden mean, a well-balanced middle ground between more extreme diets restricted either to animal-source or plant-based only foods. The rationale is that eating a large variety of foods that are in their natural form should ensure that most nutrient needs are covered. Also, as processed foods and beverages are not on the menu, it drastically reduces the consumption of harmful man-made toxic chemicals.
Indeed, many studies and clinical experience have shown the benefits of a paleo diet in relation to cardiovascular disease risk factors (weight, body fat percentage, blood pressure, cholesterol and inflammation) and chronic diseases, although more research is required.
However, as for any other type of nutrition, this ancestral way of eating must be balanced and well-formulated for optimal benefits.
The comments on vitamin and mineral deficiencies, excess carbs and food sensitivities (see the section on vegans and vegetarians in part I), saturated fats and cholesterol (section on keto), as well as on excess protein or meat intake (section on carnivores) can potentially also affect the followers of a paleo diet, but usually to a lesser extent if their diet is varied and well-balanced. So, have a look at these sections to see whether they may apply to you.
If you are unsure whether your diet is optimum, a blood test can help you determine whether any adjustment or supplementation might be required.
I have been a vegetarian for most of my adult life, until I realised that my digestive and anxiety issues, as well as my inability to lose these last few kilos of fat were due to my diet. I adopted an organic unprocessed ketogenic nutrition two years ago and never looked back. A low fat / high carb plant-based diet was just not working for me, but that does not mean it cannot work for others. I have tried not to reflect my own personal experience in this blog. Everybody is different and I do not believe that a keto diet is the solution for everybody.
No matter which diet you follow, buy unprocessed high-quality organic plant-based produces and pasture-raised animal-source foods if you can, to limit your exposure to bad inflammatory fats, added sugar, herbicides, pesticides, hormones, antibiotics and other toxic man-made chemicals. Do regular blood tests, pay attention to how you feel and be ready to adapt your diet. Even if it is common, it is not normal to feel fatigued, to experience gastrointestinal, skin or mood issues, brain fog or other conditions. Adjusting your nutrition can go a long way to help you reach your optimal health and well-being.
This article is for educational purposes only. It is not a substitute for professional medical advice and is not intended to diagnose, treat, cure, heal or prevent any disease or medical condition. See full Disclaimer here. I encourage you to do your own research and to discuss with a qualified healthcare practitioner the options that could work the best for your specific circumstances.
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