Ten true superfoods
There are many foods advertised as “superfoods” by today's health experts, almost all of them plants. In some cases this can be rather misleading, as vegetables are weighted based on their nutritional benefits and various antioxidant compounds, rather than their actual vitamin and mineral content. I'd like to break down a few of what I consider true superfoods, split between animal and plant products.
We'll start with the top 5 animal products, selected for their concentration of nutrients, and nutrient-like compounds like choline and CoQ10. Then we'll go through the plant superfoods, still focusing heavily on nutrition, but with some consideration of medicinal effects as well. Please note that if we were focusing solely on nutrient density, this list would be almost entirely animal products, including things like goat milk/kefir, eggs, and wild game as well. However, I believe in attempting to eat with a fairly even balance of animal and plant products, so I wanted this list to reflect that.
1. Salmon Roe
Salmon roe, or salmon caviar, is quite frankly the most nutrient dense food on earth. It contains significant amounts of every essential nutrient. It is also a good source of CoQ10, carnitine, taurine, choline and other bioactive compounds that are either conditionally essential or offer benefits similar to nutrients in the body. On top of that, it's a delicacy. Unfortunately the price tag may put many off. I've seen a small 2oz jar of roe cost as much as an 8oz steak, but from a nutrition perspective, the roe is honestly more valuable. That said, unless you can afford to stock up on it, it may be something to save for special occasions.
2. Beef/Bison Liver
If any list of nutrient dense foods doesn't include liver, it's not even worth considering. Coming in at a close second to salmon roe, liver is another one of the most nutrient dense foods on the planet. Different types of liver contain slightly different nutrient balance. In some cases they are so high in certain vitamins or minerals that it's possible to overdose by eating it too often! The best example of this is the liver of large ruminant animals like beef or bison. Their livers are so high in copper and retinol (preformed vitamin A) that eating them more than 1-2 times a week can cause overload of either nutrient in some individuals. That said, liver also contains good amounts of essentially every nutrient used by the human body, especially B-vitamins, so it's well-worth consuming.
Other types of liver like chicken liver still contain significant amounts of the same nutrients, but at a lower scale so they can be eaten more frequently. My personal favorite non-ruminant liver is cod liver, as it's a high food source of vitamin D, with more moderate amounts of retinol and a variety of minerals as well. It can be eaten more frequently than larger ruminant livers if desired. Some people use smaller amounts of cod liver oil as a source of certain key nutrients like vitamin D, but if you do so please be aware that only the whole liver contains the mineral and water soluble nutrient fraction.
As far as organ meats go, I'd rank heart as a close second to liver. While it's often not as high in certain key nutrients like folate and retinol, it still provides an excellent balance of B-vitamins and minerals, including much more antioxidant minerals like copper and selenium than muscle meat. Beyond that, it's also a good source of mitochondrial antioxidants like CoQ10 and taurine. Heart is very similar texturally to muscle meat, but with a more even balance of minerals, falling somewhere between muscle meat and liver in overall nutrient density. My personal favorite is bison heart, though beef heart, lamb heart, or smaller hearts like chicken or rabbit also work.
When it comes to seafood, shellfish are comparable to organ meats in their relative nutrient density, surpassing fish in most cases. Out of the different types of shellfish, oysters are the most nutritious by far. They are an excellent source of most major minerals, especially zinc, selenium, copper, iron, and manganese. As far as minerals go oysters are honestly a better source than liver! As far as other nutrients like B-vitamins go however, they are outpaced by liver and heart, though they have an excellent balance of the different B-vitamins. Similar to liver, I'd stick to only eating oysters 1-3 times per week, especially if you're consuming larger servings, as they are very high in copper. As an honorable mention, mussels are the second most nutrient rich shellfish, and contain a nice spread of vitamins and minerals, without as much emphasis on copper and zinc. Personally I consume a mix of both on different days of the week whenever possible.
5. Bone Broth
Bone broth in this case refers to any broth made from connective tissue. While bone broth isn't as nutrient-dense as some of the other animal products listed, I think it deserves a place in this list more for the sake of some of the other nutrient-like compounds it contains. Bone broth is a decent source of B-vitamins, retinol, and some minerals, but also contains a good balance of amino acids used in collagen production, especially glycine. It also contains a good balance of all 8 simple sugars used in the body (inositol, ribose, etc), and is an excellent source of sulfate ions, the preferred sulfur form in the body. Broth incorporated into the diet in soups, stews, etc, can add extra nutrition to a meal and reduce the loss of fat/water soluble nutrients during the cooking process. This is a good lecture that expands on the benefits of bone broth specifically.
6. Hemp Seeds
As far as seeds go, hemp seeds reign supreme. They are some of the lowest in anti-nutrients which normally limit most of the mineral absorption from beans, grains, and nuts. Hemp “hearts,” or shelled hemp seeds are the lowest in anti-nutrients, as in most seeds these compounds are concentrated in the shell/husk. Beyond this, hemp seeds are one of the most nutrient-dense seeds in general, and the highest in magnesium out of any plant product I've reviewed, with just three tablespoons of hemp seeds providing almost 40% of the RDI! Beyond magnesium, they provide more than 50% each of copper, iron, manganese, and phosphorus, along with smaller but still significant amounts of zinc, selenium, and potassium. As far as B-vitamins go, hemp seeds are less impressive, but still contain a decent amount of thiamine and B6. They are an extremely versatile addition to the diet overall, and can be mixed into everything from protein shakes, to soups/stews.
7. Broccoli Sprouts
While broccoli is often advertised as a very nutrient-dense, it is actually outpaced by broccoli seed sprouts. Broccoli sprouts contain an impressive variety of B-vitamins for a green vegetable, are a rich source of antioxidants (including vitamin C, vitamin E, and K1), and a decent source of selenium, phosphorus, and magnesium. Vitamin E is especially key here, as it's by far one of the most difficult vitamins to target from food, especially if you cut out wheat products, so broccoli sprouts are an excellent way to fill this gap. A 100g serving of sprouts actually provides almost 80% of the vitamin E RDI, which is even better than sunflower seeds, the prototypical vitamin E source! Recently in my own diet I've been incorporating sunflower seed sprouts as well to fill in the last 20%+.
As far as the “medicinal” benefits of broccoli and broccoli sprouts go, I'd honestly say they live up to their reputation. When chewed and digested, broccoli releases an enzyme called myrosinase which liberates beneficial sulfate ions from sulfur-containing compounds in broccoli called glucosinolates. This causes the formation of a class of compounds called isothiocyanates which have very beneficial effects on liver metabolism, and provide antioxidant and anti-inflammatory benefits. They also contain the extremely beneficial compound sulfurophane. The only downside is that the isothiocyanates compete with iodine for absorption, so make sure you're getting plenty of iodine from seafood or a low-moderate iodine seaweed (not kelp!) if you plan to consume broccoli sprouts.
I think avocado might honestly be the most underrated fruit. First off, it contains basically no sugar to speak of, while being very high in fiber and beneficial mono-unsaturated fats. It also contains a very balanced spread of all the different B-vitamins (minus B12 of course), and a good amount of vitamin E and vitamin K1 as well. It's not the highest in most minerals, but it has an even balance between them as well, and is actually an especially good source of potassium. A single avocado actually contains 3x as much potassium as an average whole banana! It's an excellent fruit to eat on it's own or mix into different dishes.
9. Potato/Sweet Potato
Despite being one of the most common food crops on earth, potatoes are actually fairly nutrient dense. They provide a fairly balanced spread of B-vitamins compared to many other vegetables, with thiamine, niacin, B6, and folate being the highest. Potatoes are also high in minerals, especially potassium, with an 8oz serving containing almost 40% of the RDI! Beyond that they are a good source of copper, magnesium, iron, manganese, and phosphorus. Potatoes are an excellent source of vitamin C, and sweet potatoes especially contain more vitamin C and antioxidant beta-carotenes than white potatoes. White potatoes do have a few drawbacks, they are a moderate source of oxalates, and belong to the nightshade family. Because of this, some individuals may find that they are sensitive to white potatoes, and that sweet potatoes or another root vegetable like taro are preferable.
Personally I'd rank dark leafy greens as an essential part of any healthy diet, and among the green vegetables kale is by far the most nutrient dense. I've often seen people rank spinach as being slightly better, but spinach is extremely high in oxalates which limits some of its nutrient absorption and can cause a number of negative health issues with long-term consumption. Kale on the other hand is actually a low-oxalate vegetable, and higher in many nutrients. While it is fairly low in most B-vitamins (like most green vegetables), kale provides a good amount of folate, vitamin C, vitamin E, and vitamin K1. It is also a decent source of a variety of minerals including calcium, manganese, copper, and iron. It is extremely low in carbohydrates, so it provides an excellent calorie to nutrient ratio, and is a decent source of fiber as well.
Similar to broccoli sprouts, a large part of kale's charm isn't in its nutrient content, but in the wide variety of other beneficial compounds it provides. It is one of the highest sources of a variety of flavonoid compounds like quercetin and luteolin, and provides many of the same active isothiocyanates as broccoli and other members of the cruciferous family. Because of this, it shows many potential protective effects against a wide variety of health conditions. Just remember that as with all cruciferous vegetables, it needs to be at least lightly cooked to avoid its active compounds interfering with iodine absorption and thyroid function.
Honorable mentions: olive oil, salmon, mussels, goat milk, eggs, taro, asparagus, flax seed, chia seed, and sunflower sprouts.
If you want to eat a diet with the full-range of every nutrient required by your body, there are a full small gaps in the list above that I'd like to briefly address. First off, most of the foods listed here are fairly low in calcium. As a result, it's necessary to include some other calcium sources. Egg shell powder, goat milk, flax or chia seeds, and certain dark leafy greens can provide enough calcium to meet this requirement. Vitamin K2, the activated form of vitamin K1, is also absent, as it is only really found in pasture-raised animal fat. Thankfully, you can either find K2 as a supplement, or include high-vitamin butter oil as a high K2 food. Vitamin K1 from dark leafy greens can be converted to K2, but this process is inefficient compared to getting most of your daily value pre-formed in animal fat.
If you aren't getting enough folate from not eating liver every day, asparagus is an excellent food source, and comes very close to making the top ten in general. Potassium can be another fairly tricky nutrient to get enough of, as it's not really present in any food in high quantity. As a result, it's a good idea to focus on a variety of the higher potassium foods like goat milk and salmon, as well as those included in the top 10. Vitamin E can be fairly difficult to get a surplus of, but thankfully it can be found in decent concentration in most shellfish, as well as in larger amounts in a variety of plant foods, with taro, broccoli sprouts, and sunflower sprouts being a few of my personal favorite sources.
Choline is another nutrient that many studies show is beneficial to get plenty of from your diet. It's what's known as a conditionally essential nutrient, meaning the body can make some choline to make up for deficiency as needed, but many studies show dietary intake still improves various health markers. Liver is the best source of choline, but if you can't eat it every day eggs should be used as a substitute, with about 3-4 eggs per day providing the entire RDI of choline for adult women, and 4-5 eggs providing the RDI for adult men. It's my personal opinion that egg whites should generally be cooked to maximize protein absorption and break down avidin, but yolks can be consumed raw if desired to minimize nutrient and fat oxidation.
Lastly, it's very difficult to get a good amount of sodium without adding salt to the diet. While the standard salt intake recommendations are fairly low, personally I look to more recent long-term evidence published by the AMA, which found the optimal salt intake to prevent cardiovascular disease to be between 3-7g per day. You can read the study here, and another study that found no clear benefit to reducing salt intake here. For this reason, I shoot for an additional sodium intake of about 1 tsp, which should equal out to something like 3-5g when you factor in salt naturally found in food as well.
I hope this article has provided some clarity on what a nutrient-dense diet really looks like. It's not difficult for us to get the majority of nutrients we need from our diets, but it does take practice and awareness of which foods are the most dense in each given nutrient. Personally, I've found that tracking your nutrient intake using an app like Cronometer can help build a better understanding of how to combine these foods on a day to day basis. I'd suggest periodically taking a week or two every so often where you strictly track your food intake, then at the end of that time period looking at your average intake of each nutrient to get a feel for where you're at nutritionally.