Non-starchy vegetables and greens
* Indicates a cruciferous vegetable
- Bamboo shoots
- Broccoli and broccoli sprouts*
- Brussels sprouts*
- Cabbage (green, bok choy)*
- Leaf vegetables (including endive and chicory)
- Leafy greens (including parsley and spinach)
- Radishes and daikon*
- Rutabagas (great replacement for potatoes in slow cookers)*
- Sauté greens (many are also brassicas*)
- Summer squash and zucchini (referred to as courgette outside the United States)
High carb vegetables and greens
The next group of vegetables present a few more challenges as they may be too high in carbs for some people - at least for now. After keto-adaption, or if starting out with a more liberal plan, add limited amounts of these but be careful with portion sizes. Weigh the portion, keeping net carbs to less than 4 grams so that the carbs in any given meal do not exceed 6 grams:
- Beets (a.k.a. Beetroot- best if it’s raw or lightly steamed)
- Bell peppers, red (more carbs than green)
- Cabbage, purple (more carbs than green
- Carrot (raw and only as a condiment, e.g. grated into a salad)
- Green Beans
- Pepper, hot varieties
- Tomato (sugar and nutrient content differs widely between varieties)
- Winter squash including acorn and butternut (limited amounts)
- Patients on anticoagulant drug therapy must ask their medical doctor about restricted foods.
Berries and fruits
Including fruits early on comes with many caveats. Tropical fruits, with the exception of small amounts of grapefruit or a squeeze or two of lemon or lime, are high in sugars. Wait until after keto-adaptation to test limited amounts of others then keep these to one or two servings per day. When eating, always include fat at the same time. For example, add cream to berries or almond butter with coconut oil to apples. Check the effect on blood glucose by testing before eating the fruit then again at one hour. Did glucose rise more than 20 mg/dL? If so, back down on the portion size.
- Berries: ¼ cup portions (~30 g) for most and half that for blueberries
- Apple: a few very thin slices- if you can’t control portion, don’t add this back
- Grapefruit: a few sections at most
- Stone fruits in season (cherries, peaches, nectarines)
Avocados, olives, and cacao
Avocados and olives are both unusual in that their flesh is not sweet. Instead, it is oily and quite rich in monounsaturated fats.
- Choose the smaller Haas avocado instead of the larger Florida variety.
- ½ of an average Haas avocado provides 2 tsp (approx. 10 g) of mostly monounsaturated fat packaged with plenty of fiber, just a few carbs, and a little bit of protein.
Olives are a great snack and the unrefined oil that’s pressed from them is also high in monounsaturated fats. These types of fats can help keep LDL low- if that’s a concern.
Cacao, the raw material from which chocolate is made, comes from the seeds of the cacao tree. Cacao percentage is often listed on chocolate bars. The higher the percentage, the fewer carbs it contains. Small amounts of high cacao chocolate (85% or higher) are keto-friendly. Bonus: cacao is high in fiber, minerals, and flavonoids. Cacao can also increase levels of dopamine- the “feel good” neurotransmitter.
Aim for high-quality sources. Whenever possible, choose meats from pasture raised or free range animals. These have a healthier fat profile than animals that are fed grains. Organic is a bonus. Most animal meats contain no carbohydrate, but eggs, shellfish, and liver do contain some carbs that should be counted as part of daily intake. (Note that even uncured bacon and sausage usually contains some carbs.)
Grass-fed vs. grain-fed meats
This is a hot topic, especially in the Paleo world- and rightly so. The fat from animals that are truly pasture-raised have a different, healthier lipid profile than grain-fed animals. In 2010, Nutrition Journal published a paper, A Review of Fatty Acids Profiles and Antioxidant Content in Grain-Fed and Grass-Fed Beef, that describes the differences. Recently the USDA Food Composition Database has started to include nutrient data on grass-fed animals.
Many of the toxins found in the environment are stored in fat, which is true for animals as well as humans. Animals that have been raised on organic feed and pasture should have fewer toxins in their fat. This is even more important in a high-fat diet than it is in a standard diet as the exposure to these toxins is greater. Bottom line: Choosing well most of the time is best but do not allow this to become an obsession. When dining out, it is unlikely that the meat will come from happy animals fed on green, toxin-free pastures. The same is true for the butter and half-and-half served in restaurants. Still, the social and emotional benefits gained from a night out will most likely outweigh any downside here.
In starting out, use familiar cooking methods. This is not the time or place to overwhelm and add the burden of sifting through the science before preparing a meal. That said, consider moist cooking such as with slow cookers (also known as crock pots). Recommended protein foods are as follows:
- Pork (including occasional bacon and sausage)
- Poultry (chicken, turkey), preferably free-range and organically fed
- Seafood (wild caught fish and shellfish but be aware of heavy metal contamination)
- Wild game meats
- Organ meats
- Eggs (farm raised and organic- or at least choose those that are high in omega-3’s)
- Dairy- this one deserves a section of its own, to follow
- Protein powders (preferably non-dairy and with less than 5 grams of glutamine/glutamic acid per serving)
High-fat dairy products, such as cream, butter, and ghee, are a staple in many keto plans. Although some people believe strongly that only raw dairy is acceptable, this presents some challenges. Raw dairy is not available for sale in many states (though workarounds include buying shares of a dairy cow). Even if it is available, the main product is raw milk, not cream or butter. It is also important to understand that there are pathogens in raw dairy, even in those coming from the cleanest operations. If contaminants are minimal, most healthy people may not be affected but the same pathogens may be a disaster for individuals with a compromised immune system which it often true in those with cancer.
It is well-documented that dairy fats contain estrogen metabolites (estrogen-like compounds). What is less clear is what effect these have. In theory, estrogen (a protein) should be dismantled during digestion similar to other proteins but there are some holes in this argument; mainly, digestion and absorption are clearly impaired by leaky gut syndrome and/or through the drugs commonly used to treat cancer. If the plan includes high-fat dairy, choose from these products:
- Butter (including ghee and clarified butter)
- Heavy whipping cream (preferably without mono- and diglycerides or polysorbate 80)
- Sour cream (cultured, without added starches or fillers)
- Full fat cream cheese (again, look for fillers, including whey protein)
- Some hard or ripened cheeses (1 oz. or less per serving-count the protein as well)
- Milk and cottage cheese is not keto-friendly. Note also that while seemingly thick in consistency, most Greek yogurt is too low in fat and too high in protein for the purposes of this diet.
Dairy proteins have an entirely different set of issues. They are anabolic, meaning that they are intended to stimulate growth. This makes perfect sense given the reasons that mammals, including humans, produce milk. Among the many hormones in milk that are associated with growth is insulin-like growth factor 1 (IGF-1). IGF-1 is crucial in childhood as it works in harmony with other growth factors and hormones important to overall growth and development. There is yet another issue that is rarely included in the discussion of dairy proteins in ketogenic diets. Both whey and casein, the two main proteins found in dairy products, stimulate a release of insulin independent of a rise in glucose. What this means is that dairy proteins directly stimulate the pancreas to produce insulin. Again, this is a great evolutionary advantage for young animals in a growth phase but a poor idea in those who have cancer.
The Casein conundrum
It is clear that for many people casein is inflammatory and may elicit an unhealthy immune response or exacerbate leaky gut syndrome. Naturally, any of these issues is problematic for anyone, either with or without cancer.
Casein and dairy allergies
True dairy allergies provoke an immune response. In cases of immune-mediated casein allergy, all sources of dairy proteins should be eliminated, including those with negligible amounts, such as butter. However, with suspected sensitivity rather than allergy, a two week elimination diet that leads to improvement in symptoms may guide the decision as to whether or not casein should be excluded.
Casein allergy vs. lactose intolerance
There is a clear distinction between casein allergy and lactose intolerance. While casein allergy provokes an immune system response, lactose intolerance is due to insufficient production of the enzyme (lactase) needed to break down the bond in lactose that links glucose to galactose. Without sufficient production of this enzyme, lactose ferments in the gut, causing bloating and diarrhea which leads people with lactose intolerance to believe that their bodies are incapable of dealing with any dairy products. However, high-fat dairy and keto-friendly cheeses contain only small amounts of lactose and most people retain enough ability to digest these amounts with no gastrointestinal distress.
Nuts and seeds
Nuts and seeds offer many opportunities to increase fat intake on a keto plan. There are so many different ways to enjoy nuts such as whole, chopped, nut butter, or nut flour. Nuts also travel well. This category does come with caveats, though. For one, it’s very easy to overeat them- and since they contain carbs and protein as well as fat, “just a handful” can add up quickly. Also, some—like pumpkin, sesame, and sunflower—are relatively high in pro-inflammatory oils. Choose carefully and use these sparingly, more like a condiment. Others- such as ground flaxseed, chia seed, and hemp hearts- are high in healthy fats and fiber. Add them to salads, puddings, shakes, and baked goods; the fats they contain are very healthy and they’re a great source of fiber as well. Using these will also help keep your omega-6 to omega-3 ratio in a healthier range.
Eating lots of nuts, especially almonds and other varieties that are high in oxalates, may raise your risk of kidney stones. It may be best to limit intake (including all forms) to a maximum of 4 oz. (112 g) total per day. (Athletes may need to eat more in order to keep up with their high energy demands.)
Keep to the following short list of keto-friendly nuts and seeds. Add to it after keto adaptation. Research favorites and evaluate the pros and cons of each in light of the information about oils, oxalate levels, and antinutrients (including oxalates and phytic acid). There is also considerable debate about how best to consume nuts: raw vs. soaked vs. sprouted. Rotate choices to lessen the chance of developing a sensitivity to any one variety. Choose from this list:
- Almonds (including almond butter, flour, milk)
- Brazil nuts (rich in selenium but limit these to 2 nuts per day- excess selenium may be problematic in cancer and Brazil nuts also contain small amounts of radium)
- Macadamias (great choice- high in good fats; low in carbs and protein; low in oxalates)
- Walnuts (good choice- fewer omega-6’s than most nuts)
- Chia seeds (rich in healthy omega-3’s and fiber- refrigerate)
- Hemp hearts/seeds (rich in healthy omega-3’s and complete protein)
- Flaxseed (rich in healthy omega-3’s and fiber- grind and store in the refrigerator)
- Coconut (includes coconut cream, butter, unsweetened meat, flour, and boxed milk)
- Coconut is not a true nut but it is included here to simplify the list. Be especially careful with coconut water; it is relatively high in coconut sugar, so not part of a keto plan.
Fats and oils
Keto diets are very high in fat so quality, composition, and balance is extremely important. Best practice is to use a combination of animal (and fish) fats, coconut oil, medium-chain triglycerides, monounsaturated oils (olive, avocado), omega-3 oils (from ground flaxseed, chia, hemp hearts, fatty fish, fish oil) and omega-6’s (limited amounts, preferably from nuts and seeds, not oils).
When choosing oils, always look for cold-pressed, organic, and unrefined varieties- that’s not a guarantee of quality but at least it’s a step in the right direction. (Avocado does not have to be organic.) Read labels and avoid any products made with refined (which means solvent-treated) oils extracted from GMO plants such as soybean, canola, corn, and safflower. When sautéing or stir frying, use lard or other animal fat. If using coconut, olive, or avocado oil, keep heat below the smoke point and cooking times short. Also ventilate well to avoid breathing in the airborne byproducts of fat combustion: If the airway is irritated, the temperature is obviously too high.
It is also good practice to use track intake of fats and oils using software or an online tool, such as Cronometer. This will aid in assessing the all-important omega-6 to omega-3. Unfortunately, this is no guarantee that the body is metabolizing oils optimally- only tests ordered through an integrative practitioner can determine that. Choose your fats wisely from the following list:
- Lard, tallow, and other animal fat (such as duck fat) – preferably from organic, pasture-raised animals. Be careful, as the food industry has jumped into this market and you’ll find cheap but unhealthy hydrogenated varieties on supermarket shelves.
- Butter or ghee- buy the best quality that you can afford- preferably from grass-fed animals living on organic and sustainably-maintained pasture.
- Coconut oil and MCT oil
- Omega-3 fish oils, either as fresh fish (e.g., wild caught salmon), krill oil, or in molecularly distilled supplements that are high in DHA
- Omega-3 oil from non-animal sources (get this from seeds, such as flax, chia, hemp)
- Extra virgin olive oil (cold-pressed and organic) or oil from olives grown, processed, and packaged by California growers (which bypasses theadulteration issues seen in many of the imported brands)
- Avocado and macadamia nut oil, also high in monounsaturated fat
- Salad dressings and mayonnaise- organic or homemade
- Buttery Spreads such as MELT® or (non-soy) Earth Balance®- non-GMO and organic- especially if you need a substitute for dairy fat
- Other oils used in much smaller amounts, primarily to add flavor (e.g. sesame oil or infusions using garlic or chili)
It’s impossible to overestimate the importance of lowering the “sweet thermostat”. That is the level at which sweet foods satisfy both mentally and physically. A low setting will ease compliance to the new plan as it reduces the seductive hard-wiring in the brain that can trigger a sweets binge. (Evolutionary biologists suggest that there was a time when sugar-seeking behavior conferred a survival advantage by allowing for more fat storage.)
Spices, seasonings, and those “extras”
Spices and seasonings add more than just variety and interest. Some (like curry and turmeric with black pepper) have anti-inflammatory properties while others (like cinnamon) are known to lower blood glucose. Feel free to add the following spices to any dish:
- Black pepper
- Cayenne pepper
- Chili pepper
- Coriander seeds
- Cumin seeds
- Mustard seeds and prepared mustard
A word of caution- be careful with commercial spice mixes as they often have added sugars or starches (flow agents) so read all ingredient labels carefully.
- Traditional condiments, such as mustard and ketchup, need to be screened - check labels for sugars and carbs. Standard ketchup is high in added sugars, either as cane sugar or high fructose corn syrup.
- Choose gluten-free tamari over soy sauce (the added bonus: it also has fewer carbs).
- Add a good squeeze of lemon juice to food! (Count the carbs if using more than one tablespoon per day.)
- Vinegar, such as apple cider (with or without “the mother”) can slightly suppress a rise in glucose. Experiment with vinegar infusions, such as savory Italian herb, or spicy chili, ginger, or turmeric! Be careful here, though, as too much (hard to define) can acid-etch tooth enamel (rinse with water afterwards) and may have a downside on digestion. Also, avoid using balsamic or malt as these are too high in sugar.
- Many people choose to use extracts, such as orange oil, to flavor treats. And finally, avoid any seasoning that lists monosodium glutamate (MSG) or any type of hydrolyzed vegetable/soy protein. These are only found in poor quality foods.
Salt is so important that it deserves its own mention. The ketogenic diet changes the way that the kidneys handle sodium so more ends up being excreted in urine. Also, intake of sodium may drop simply by cutting out sodium-laden packaged products. The combination of more excretion and less intake may present as “keto flu”. Add some salted bone broth as that contains other needed electrolytes as well. The current trend is to move away from conventional iodized salt and towards specialty versions, like sea salt.
Baking powder and baking soda
Both of these are keto-friendly and commonly used in baking. Baking powder contains some carbohydrate and possibly aluminum as well (check the label). Baking soda (sodium bicarbonate) is carb-free and never contains aluminum.
The best liquid is water. Keep in mind that the ketogenic diet is slightly dehydrating so be sure to drink enough to replace fluids and electrolytes that are lost throughout the day. Beverages other than water add variety. Some options:
- Sparkling water and club soda (note that club soda contains sodium bicarbonate)
- Herbal tea (check the label ingredients for “natural flavorings” or other potential source of carbs)
- Stevia sweetened drinks are okay but read the label carefully to be sure that they do not also contain artificial sugars, such as aspartame or sucralose
- Unsweetened almond, hemp or flax milk are low in carbs and may be used as a base for high-fat shakes (watch for added calcium carbonate which can contribute to constipation)
- Unsweetened boxed coconut milk. (Note: this is not the same as the canned coconut milk used in Asian cooking)
- Coffee and tea (test for its impact on blood glucose levels)
Compare pre-coffee blood glucose level to the level 30 minutes later. Does that level spike by 15 mg/dL or more? If so, modify it. Consider adding cream or turning it into a “Bulletproof” drink (coffee spiked with fats, such as ghee and medium-chain triglyceride oil). This is keto-friendly as well as a way to add some needed fats for the day.
Children: exceptions to the rule
Children following ketogenic diets should feel special, not uncomfortably different. This usually means offering them beautiful and tasty treats that replace their former favorites” – “training wheels”* – as they make the transition. Still, work at resetting their thermostats as well.
*Personal note from Justin Wilford, co-founder of the MaxLove Project for children with life threatening illnesses.