This post was inspired by Rob’s Soylent experiment. He recently got a lot of press for constructing an almost completely artificial liquid diet containing everything a human needs and then consuming this goo exclusively for a month.
Yes, of course it has been done before, but I thought the idea was interesting and wanted to try it myself. I am very interested in health and longevity, so I thought I’d incorporate what I consider the most important and well-founded dietary findings in my recipe. The final recipe (let’s call it “Goop”, like the food in The Matrix) will be quite cheap compared to regular food and include only natural vegetarian ingredients and a multi-vitamin (mostly for the vitamin D).
Nutrition is complicated. The most difficult part of any new dietary idea is that humans are extremely long lived, so it takes forever to verify the long-term effects. Also, most of us are not keen to be put in cages and fed on a rigorous schedule, so you never know quite what people really eat. You can probably tell a lot from mouse studies and you can monitor known health markers in humans, but there are no guarantees. I have not even tried this diet myself yet (though I will in just a few days). If you decide to give it a try, you do it completely at your own risk.
Even if you are not interested in my final recipe for a complete nutrition shake (or shake-like substance), you might find the general discussion on what to put in your body interesting.
My goal is to design as “healthy” a diet as possible, which is at the same time as simple as possible. Palatability comes a distant third. My plan is not to consume Goop exclusively for the rest of my life, but perhaps to consume the majority of my “meals” this way. I don’t want to give up on sublime culinary experiences or that ice cream that just hits the spot once in a while. The majority of my meals or snacks currently do not fall in those categories, though. Partly it is also a fun intellectual excercise.
I currently do intermittent fasting once or twice a week. Even though it is probably just as healthy to allow yourself to eat a few hundred calories during those 24 hours, to me, it just complicates matters. It is psychologically easier just to say “stop” for 24 hours than to bargain with yourself over how much food you are allowed to eat on your fasting days. I suspect the same might be true with food intake. If your diet is extremely simple and restricted, it might be easier to follow than one with a hundred vague guidelines which will give you tastier food and more variation, but many more daily decisions and temptations.
It may also be a starting point for a later diversification or for optimizing in the “palatable” direction. We’ll see.
How many calories you need is obviously a function of many variables, including gender, age, height, physical activity and genes. Fortunately, too many or too few calories are quite easy to detect. Just weigh yourself regularly. Preferably on a scale that measures body fat percentage. I know those are not very accurate, but here we do not care much about absolute numbers, just change.
The simplest, most researched and most effective diet tuned for health and longevity must be calorie restriction. Eating 10-30% fewer calories than you “need”, but all the nutrition. With Goop, CR with full nutrient intake becomes easy. I will practice a mild CR, because full-blown CR is inconvenient.
I am almost 2 meters tall and I burn 500-600 calories a day biking to and from work. I also run regularly and do some strength training. I need more calories than most, but let’s start out with the usual assumption of a target around 2000 calories.
We get calories from protein, carbohydrates and fat. How much you should get from each group is a source of fierce debate. The safest bet seems to be that carbs should be somewhere between 30% and 50% of daily calorie intake, fat around 30% and protein between 15% and 30%. That is generally less carbs than in a regular western diet. On the other hand we are not aiming for so few carbs as to induce ketosis which may help people lose weight somewhat faster, but does not seem generally conductive to health.
Eating too much protein can also be unhealthy. The liver and kidneys are put under strain and you may lose calcium and thus bone mass. You have to make sure you drink a lot of water and adequate calcium if you consume 1/3 of your calories from proteins. In the very well researched Fantastic Voyage, Ray Kurzweil and Terry Grossman advocate 35% of calories from protein in general and 55% for the rather extreme diet for those with diabetes II. Eating more protein than 1g/kg body mass will not make you gain muscle faster.
When it comes to fat, it is probably good for you to have ratio of Omega 6 / Omega 3 consumption somewhere between 2:1 and 1:1. The modern diet has way too much Omega 6, which is inflammatory and bad for your heart.
Regarding carbs, we want to have slow carbs that the body digests slowly. This helps your body keep your blood sugar and insulin levels steady, which protects you from diabetes and wards of hunger. In a normal diet we also want a lot of fibers. Fibers makes you digest more slowly and feed your intestinal bacteria. If you are not used to food with high fiber content, you need to increase fiber intake slowly, since you need to build up your gut flora. Goop contains 50-60 grams of fibers each day, which probably takes some getting used to. A common guideline is that your diet should contain at least 30g fibers per day.
When it comes to protein, things get a little tricky. Normally you would just want protein with an amino acid profile close to your own, which makes meat, eggs or whey protein powder a good choice, unless you are lactose intolerant.
Calorie restriction, see above, seems to induce slower aging. Interestingly, so does protein restriction, with some caveats. Even more intrestingly, restricting just the amino acid methionine (a part of normal protein) also seems to induce slower aging (see methionine restriction). Methionine is an essential amino acid, so we can’t just cut it out of our diet, but restricting it is possible, by eating certain vegetarian proteins and not too much of them. Soy is one protein source that has comparativel little protein. It has gotten some bad press, but it is probably safe. Nevertheless perhaps pea protein is the most attractive alternative.
Long term methionine restriction is AFAIK completely untested in humans, so I wouldn’t advocate it or try it myself. I do think it is prudent to make sure you don’t get excess methionine, though.
Intermittent fasting and carb concentration
I practice intermittent fasting (IF) once or twice a week, fasting 24 hours on water and green tea. The evidence for the benefit of different kinds of IF, both in animal studies and humans (think religious fasting) has reached a thoroughly convincing level.
The first 1 - 3 times I was really hungry, but the body quickly adapts and it becomes easier. There is however an alternative possibility, which may give the same benefits. Carbohydrate-concentration. Instead of fasting, you only carb-fast. That is, you consume all of the carbohydrates for each day in one meal. It does not matter which one.
Carb concentration is less well researched than intermittent fasting, but the effects on blood sugar are fairly well understood and it looks promising. I might try carb concentration and see how convenient it feels, since it is quite easy to divide the components of a shake anyway one sees fit. It is not something I will try immediately, though.
We need vitamins to live. It is fairly well-known how much we need to survive, but the optimum levels are a source of debate. Many (probably all) vitamins are anti-oxidants, protecting your body from free radicals. According to the free-radical theory of aging, this should be very important. At the same time studies don’t really find life-extending effects from consuming large amounts of anti-oxidants. At the same time, meta-studies that have found deterimental effects seem quite silly, e.g including patients that take large quantities of vitamins for some serious ailment.
Here is a list of the recommended daily allowances.
If we cover the vitamin need with a multi-vitamin, it is probably best to take it in divided doses with “meals” (at least fat), for proper uptake. There are multi-vitamins made to be taken in divided doses, for example these [Two-per-day capsules] (http://www.lef.org/Vitamins-Supplements/Item01714/Two-Per-Day-Capsules.html). Otherwise you can just split one, if it is dry.
Almost all multi-vitamins come with the alpha form of vitamin E, which some say is a problem. This might displace the other forms of vitamin E, and actually make you deficient. In Goop, I will get plenty of gamma-tocopherol from the flaxseed oil, so it is probably OK. Also, this nutritional researcher notes that it might be a confusion of cause and effect and that low gamma-tocopherol may just be a indicator that something else is wrong.
Vitamin K is not a part of most multi-vitamins, so we need that through our diet.
Here are the RDAs for minerals. You could get most of them from a decent multi-vitamin, but those below usually need other sources.
Phosphorus deficiency is very rare, so there are almost no phosphorus supplements for humans (but plenty for horses).
Calcium is usually not included in a mutli-vitamin in enough quantities, just a little to go with the vitamin D.
Potassium is a lethal poison if you consume too much of it, so you have to be very careful when supplementing. This is why potassium pills are rare and usually far below the RDA.
Iron is an oxidant, so you don’t want to get too much. You also don’t want to be deficient, making you anemic and lethargic. Menstruating women need more than men.
Copper, like iron, should not be consumed to excess. I have never seen a multi-vitamin with more than 50% RDA (RDA is 2g) copper.
Sodium and chlorine are easily obtained from table salt. Most things get tastier with a little salt anyway.
Phytochemicals (or phytonutrients) are difficult. They are the tens of thousands of possibly protective substances in plants. They are not absolutely essential to life, but they may protect against cancer, stroke, macular degeneration, inflammation and all sorts of things.
It is very difficult to come to some sort of conclusion. The effects are certainly not obviously beneficial. Carotenoids, resveratrol and glucosinolate seems the most interesting, to me, though especially resveratrol is controversial.
The matter is further complicated by the issue of hormesis. Protecting from oxidant damage is good, but if you protect too well it seems to make it worse. For example, the positive effects of excercise (which inflicts oxidation damage to your body) can be negated by anti-oxidants. It seems that only if you stress your cells just enough, good things happen.
In my personal opinion hormesis is the single most confounding factor of longevity science. It is just like with training a muscle. If you train it too much, you may overtrain and it becomes weaker instead of stronger. If you don’t get any oxidative stress, you don’t “train” your body and trigger the beneficial heat shock responses and gene expressions, but if you get too much you “overtrain” and just break down your cells. Since so many different things adds oxidative stress and so many other things protect from it and since it seems almost impossible to know (I suppose blood tests could one day be developed) if you get too much or too little, it is very hard to know what anti-oxidants will do to your body.
The actual recipe for one day
Where possible and not too expensive, I will use organically grown ingredients, to avoid pesticides. I don’t think the benefit is large, so I won’t go to special stores or pay a premium of more than 10% or so. Oat, broccoli, berries and tomatoes are the ingredients below that I think might benefit from not having pesticides.
500g plain 3% fat, unsweetened yoghurt or sour milk
This adds protein, calcium, potasisum and some possibly beneficial gut bacteria.
300g oat brans
This is the main source of low GI-carbs, copper and iron. It is also a good source of phosphorus and potassium. The fiber will make you feel satiated longer and in particular the beta-glucans in oat, which lowers cholesterol, in particular LDL. According to the Wikipedia link above, beta-glucans may also boost your immune system and have some anti-cancer properties. Also, it is a whole-grain that contains no gluten, which is trendy to avoid even amongst non-celiacs because of its allegedly inflammatory nature. I don’t think the final verdict on gluten is in yet. Bear in mind, though, that some people with celiac disease are also allergic to oats.
40g flaxseed oil
This is the main source of fat and that which restores the Omega 3 - Omega 6 balance. Flaxseed oil is a rich source of alpha-lipoic-acid and some people take it as a nutritional supplement. Strongly anti-inflammatory.
150g is supposed to be the average weight of one stalk of broccoli. Exact dosage is not terribly important, but it is the main source of vitamin K, so not below 75g. Broccoli is a “leafy-green”, which counts as the most healthy of the vegetable families. It is rich in phytosterols, which fight cholesterol. It also mildly anti-inflammatory.
Almonds control blood sugar and makes you feel full longer. Mildly anti-inflammatory.
Besides the five main ingredients, I have also added four flavorings.
10g cinnamon, which is most famous for regulating blood sugar and lowering LDL.
20g cocoa powder, which are rich in flavonoids, are linked to health benefits like lowering coronary heart disease and stroke risk. Also it tastes nice.
10g sun-dried tomatoes. 10g is about five dried tomatoes. I suppose I could use fresh tomatoes as well, but the drying process preserves the nutrients and makes them easier to transport and handle. Tomatoes contain lycopene. Tomato consumption has been associated with decreased risk of certain cancers.
100g frozen unsweetened berries. Mostly bilberries, but any berry will do. Full of phytochemicals.
I don’t know yet how I will mix these flavorings. Perhaps I will just throw them together. Perhaps I will keep them in separate meals.
If it needs to be sweeter, I will add stevia which must be far and away the best sweetener. Wikipedia: “Current research has evaluated its effects on obesity and hypertension. Stevia has a negligible effect on blood glucose, and may even enhance glucose tolerance”.
Goop contains very little salt, so I’ll need to add 5-10g. How much salt you lose when working out seems to vary between individuals, but you lose roughly 1g per liter sweat and sweat roughly 1 liter from a 1 hour run. 30-50% of the population are sensitive to too much salt and may get high blood pressure. For the rest, it does not seem to make a difference.
The RDA for minerals are easy enough to satisfy, but vitamin D is damn near impossible to get enough of from natural sources. The only possible exception is fatty fish, but I don’t want that in a shake… If you live in a dark country and/or spend your working hours inside, like I do, getting enough vitamin D is even more important. Goop as it stands, also lacks vitamin A, but that could be easily remedied with a carrot a day. I will take a daily multi-vitamin, but with a carrot, that could probably be downgraded to just vitamin D.
Vitamin C is unstable over time in the presence of water and I think others may react with iron, so it is probably best not to add vitamins to the mix, but swallow them separately.
Goop contains loads of soluble fiber, which amongst other things is good for lowering cholesterol. The high fiber content (56g) means that my stomach will have to get used to it gradually, by building up suitable gut bacteria. It also means that I have to drink a lot of water.
Adding it up
This comes to 2131 calories per day, with 198g carbs, 105g fat and 76g protein. The food is very anti-inflammatory and has a low glycemic load. The oat bran I use seem to have a slightly different nutritional value than those in the databases, so YMMV.
For a physically active male, even if he would want mild calorie restriction, this is probably too few calories. There is room for adding more carbs and protein, but preferably not more fat. Fruits, carrots, beans, protein powder and lean meat are possible additions. I suppose recovery drinks or bars after exercise is one simple, if somewhat expensive and sugary, way to compensate with more carb and protein calories. I will experiment a bit with this.
If I wanted less calories, let’s say for dieting, I would cut up to half the almonds, half the flaxseed oil and 100g of the oatbran. It is not supposed to be healthy to lose more than 0.5 kg (1 pound) per week, which is about 600 calories per day below your normal intake, so don’t go overboard.
I will just mix the ingredients and some water together to a shake or drinkable substance. I will try to mix just a little, since a smooth goo would raise the glycemic index. I still want to see oats. For variation, oat brans (say 200g), water (3 dl, pour over when boiling), oil (at most ½ dl), stevia and cinnamon or cacao as a flavouring can be blended (once again, not too smooth) and spread thinly and baked in the oven in 150 degrees C for 50-60 minutes, for a dry, not quite delicious but nutritious cookie. Since it is dry, it will be edible for many days. The low temperature will not oxidize the oil or destroy other nutrients.
I will also eat sugar-free gum after meals, to make sure that my gums get some workout. Also a clean mouth is imperative for a healthy heart.
As an experiment, I will consume Goop exclusively for a few weeks (at least three) and measure blood pressure, weight, body composition (if I can find my body composition scale), resting heart rate, mental ability, athletic ability and general well being continuously. A few people I know have expressed interest in doing the same. It would be interesting to measure various markers from my blood as well. Unfortunately, where I live this is not really offered as a separate service but rather as part of a complete health exam, which is quite expensive to do twice in succession. I will probably do it afterwards, though.
I will not go cold turkey from normal food immediately, but increase gradually, mainly to make sure I can handle the fiber content.
Adding nootropics and stimulants, like the original Soylent guy did, is also interesting. However, to avoid complicating things, I will add this later. I don’t really know which substances, but at least ginkgo biloba.