Tag Archives: food

Free food for health and the environment

To motivate choosing vegan or environmentally friendly or healthy food, one option is to provide it for free. If people have eaten their fill, they are less likely to buy extra, whether meat or unhealthy. There are tradeoffs of course – any free resource tends to be overused.

For free food to be environmentally friendly, it should not be wasted and disposable utensils should be avoided. Food waste can be reduced by providing small portions to be eaten on the spot, with unlimited free refills of these small portions. All-you-can-eat restaurants already use this strategy by providing only small plates and bowls. The oversight of the food servers and other eaters and their disapproval of wasting food is a social deterrent.

The use of disposable dishes may be reduced by not providing any, requiring people to bring their own utensils, but some will then bring disposable and some will substitute away from the free food toward buying (unhealthy, delivered) meals in disposable containers. It is an empirical question whether the potential use of disposables outweighs the benefit of switching people to healthy and environmentally friendly eating. A dishwasher next to the food station eases the use of reusable kitchenware. Handheld foods (buns, sandwiches, wraps, whole fruit) do not require dishes.

Free food may lead to overeating and increase obesity. Any free resource tends to be over-used, especially if in limited quantity or available for a limited time. The latter overuse motives are eliminated by making the free food continuously available, but this exacerbates potential overeating. The obesity effect can be reduced by offering only healthy food without the somewhat addictive additives sugar, salt and monosodium glutamate. Foods like celery, iceberg lettuce, whole linseeds that provide fewer calories than it takes to chew and digest them (given inefficient human digestion, as opposed to the calories measured by the burn method) may actually reduce obesity when distributed for free. Again, it is an empirical question whether the potential costs of overeating and obesity neutralise the benefit of substituting towards healthier and environmentally friendlier foods.

Given how cheap basic healthy foods are (rice and other dry grains under a dollar per kilo, cabbage, bananas, lemons, dry peas and lentils two dollars per kilo), the social benefit of providing these for free may outweigh the deadweight loss of taxation to finance their purchase. In this case, the government would actually save money in the long run (over the average life expectancy) by offering free food. Cooking the foods would increase the costs slightly, but not much if it is done continuously in bulk by machines (rice cookers, bread machines). No need to wash the cookers if a new batch goes in within hours and the heat sterilises the machine. Or the machine can wash itself if it is connected to a water supply, a drain and a soap dispenser and either has a mixing blade in it like a blender or the water supply has sufficient pressure to flush out the soap residue.

Asking questions of yourself

To make better decisions, ask about all your activities “Am I doing this right? Is there a better way?” I would have benefited from considering such questions about many everyday tasks. For example, I brushed my teeth wrong (sawing at the roots) until late teens, brushed my teeth at the wrong time (right after a meal when the enamel is soft) until my 30s. I only learned to cut my own hair in my mid-20s, and this was the highest-return investment I ever made, because a hair clipper costs as much as a haircut, so pays for itself with the first use.

Peeling a kiwi with a spoon is far easier than slicing with a knife. All it took to learn this was one web search, but it required asking myself the question of whether I was peeling fruit optimally. Same for extracting the seed from an avocado.

Cracking the shell of a hard-boiled egg, making two holes at the ends and blowing air under the membrane before peeling is another trick I wish I had known earlier.

Microwaved food is cooler in the centre, so to avoid scalding one’s mouth, it is helpful to start eating it from the middle. Cooked food left in a covered cooking pot or transferred to a storage container while still mildly hot does not go bad at room temperature for several days – doing this experiment required posing this hypothesis. Drinking without touching the bottle with one’s mouth turns out to be quite easy and is widespread in India.

Only after learning to drive did I start meaningfully using gears on a bicycle, and it took about 15 years more to start shifting approximately correctly (pedalling cadence 60-100 rotations per minute, downshifting before stopping, avoiding cross-geared riding). Similarly for basic bike maintenance like cleaning and oiling the chain, selecting the appropriate front and rear tire pressure given one’s weight and tire widths. Seat height is one thing I figured out early, but not handlebar height.

As a teenager, I would have benefited from asking myself whether I was overtraining, whether my nutrition was reasonable, how soon to return to training after various injuries and whether to seek medical assistance with these. Questioning the competence of coaches and doing a simple web search for sports medicine resources would have prevented following some of their mistaken advice.

Sometimes asking yourself the question reveals that you are already doing the task correctly. On the internet, people claim that they do not use shampoo, just water, and their hair stays clean-smelling and more lush than using detergent. An experiment not to use shampoo was a failure for me, causing greasy hair and lots of dandruff after a few days. The optimality of shampoo may depend on individual scalp and hair characteristics. On the other hand, a single-blade disposable razor and cold water give me a better shave than multi-bladed fancy brands with foam (that get clogged), and the disposable razor stays sharp enough for a month or two of everyday shaving.

When going to teach, it may be worth asking whether the room is the correct one, even if some students show up and the room is free, because once in this situation I was in a room with the right label, but in the wrong building.

On the other hand, constantly doubting oneself is unhealthy and unhelpful. If enough evidence points one way, then it is time to make up one’s mind.

Food calories are not directly related to obesity

It seems that the change in bodyweight should be a strictly increasing function of calories eaten minus calories spent. The first caveat to this claim is that calories in the food eaten do not equal the calories absorbed, which is what matters for weight gain. People differ in the efficiency of their digestion – that is what bariatric surgery relies on. Also, food labels use calories measured by the burn method (dry the food, burn it, measure the heat output), which ignores for example that coarsely chewed food chunks pass through the digestive tract relatively unchanged, thus contribute few nutrients to the organism. An extreme example is wholegrain flax (linseeds) that remain undigested due to a waxy coating. In nature, seed dispersal by birds relies on the indigestibility of the seeds.

Even if calories absorbed could be accurately measured, the type of food eaten would still matter for weight gain due to imperfect willpower. Some foods are more addictive than others, notably those rich in refined carbohydrates – an easy example is drinks that are essentially sugar-water. Consuming a given amount of calories from high-glycaemic-load sucrose makes people eat more sooner on average than ingesting the same calories from slowly digested whole grains or unsaturated fat. Similarly, ignoring willpower limitations is why abstinence-based programs to prevent sexually transmitted infections, which naively might be expected to be 100% effective, are in fact ineffective (Underhill et al 2007, doi:10.1136/bmj.39245.446586.BE).

There are various tricks to circumvent limited willpower to win the game against one’s future tempted self. To reduce temptation, food should be out of sight outside mealtimes (in cupboards, drawers, fridge) and unhealthy snacks should not be bought at all. Even seeing dishes and cutlery may trigger cravings, in which case these too should be placed out of sight when not in use.

Avoiding grocery shopping while hungry is an old piece of advice, which may be taken further by having someone else buy your food. Two people can even agree to grocery-shop for each other according to shopping lists exchanged beforehand. Online ordering may be a solution, but of course the merchants want customers to buy more, so advertise tempting foods with photos on their website. These ads can be blocked with some effort. A more sophisticated solution is to have one’s own user interface (front end) interact with the merchant’s website – scrape the data on inventory and prices, send commands to buy.

Seasonings may reduce the variety of diet

Animals may evolve a preference for a varied diet in order to get the many nutrients they need. A test of this on mice would be whether their preference for different grains is negatively autocorrelated, i.e. they are less likely to choose a food if they have eaten more of it recently.

Variety is perceived mainly through taste, so the mechanism via which the preference for a varied diet probably operates is that consuming a substance repeatedly makes its taste less pleasant for the next meal. Spices and other flavourings can make the same food seem different, so may interfere with variety-seeking, essentially by deceiving the taste. A test of this on mice would flavour the same grain differently and check whether this attenuates the negative autocorrelation of consumption, both when other grains are available and when not.

If seasonings reduce variety-seeking, then access to spices may lead people to consume a more monotonous diet, which may be less healthy. A test of this hypothesis is whether increased access to flavourings leads to more obesity, especially among those constrained to eat similar foods over time. The constraint may be poverty (only a few cheap foods are affordable) or physical access (living in a remote, unpopulated area).

A preference for variety explains why monotonous diets, such as Atkins, may help lose weight: eating similar food repeatedly gets boring, so the dieter eats less.

Adapting to a low-salt diet is quick

Overconsumption of salt is a significant public health problem. People are reluctant to reduce the saltiness of their food, because it would taste bland. Eventually, preferences adjust so that a diet without added salt tastes normal and salted foods are perceived as too salty. The only question is how quickly tastes adapt.

My experience of stopping adding any salt to my food was that the bland taste lasted less than 3 days, after which I had fully adjusted to the new reduced level of saltiness. An easier way to adapt may be to gradually reduce the amount of added salt, as opposed to suddenly cutting off all of it, as I did. In that case, there may be no perceived taste difference, especially if the reduced salt is accompanied with increased amounts of other seasoning, like pepper. Given the smallness of the adjustment cost and the health benefit of cutting salt consumption, doing it is a clear and easy win.

Delivered food and restaurants are unhealthy due to moral hazard

Consumers observe the taste and cost of food directly, but checking the ingredients for healthiness takes extra effort and time. Rational inattention then implies that eaters are unlikely to verify the health claims. Thus food suppliers are subject to moral hazard: consumers buy based on the healthiness they expect, not the actual ingredients the seller chooses, so the seller has an incentive to improve taste, reduce the production cost and cut price even when this makes the food less healthy.

The standard solutions to moral hazard from economic theory are verification, repeated interaction and vertical integration (selling the firm). In the context of food, safety standards and truth-in-advertising laws restrict the substances manufacturers may add and claims they can make. Regulators verify claims made and punish for illegal additives or false advertising. Also, if a food supplier is found to use unhealthy ingredients (or amounts of sugar, salt and fat), then some consumers may switch to alternate providers, which is a repeated game punishment for the original seller.

The weakness of both verification and repeated interaction is imperfect monitoring: small increases in unhealthy substances are difficult to detect, because tests are noisy and food composition varies naturally. The variation sometimes makes the amount of an ingredient exceed the healthy limit, so honest suppliers would also be punished with positive probability. Incentives are created by the difference in payoffs, so reducing the payoff of the honest decreases their motive to stay honest. The imperfect monitoring allows unscrupulous sellers to outcompete the providers of healthy food on taste and price, for example by using various tricks to circumvent the legal requirements on labelling (https://sanderheinsalu.com/ajaveeb/?p=728).

The remaining solution to the moral hazard problem is vertical integration of the buyer and the supplier, i.e. home cooking. Of course, the ingredients bought to be cooked at home are subject to similar moral hazard – unhealthy substances can be added at any stage of the production process. The risk could in principle be even larger than for processed foods and restaurant meals, but in practice, it seems that simple and unprocessed ingredients are more difficult to manipulate than prepared meals, which are a mixture of many components. Adding sugar, salt, fat or monosodium glutamate to flour, rice or dry beans without mentioning it on the nutrition label is easier to detect than the same (amounts of) additives in shrimp fried rice, bread or a burrito. Raw meats and fish do have extra salt and food colouring added, but usually less than for ready-to-eat meals.

Relative prices are another reason why there may be less manipulation of ingredients than processed foods. There is a per-unit cost of adding unhealthy substances, as well as a fixed cost due to the risk of lawsuits and fines, especially if the additives are not declared on the label. Unprocessed ingredients are less differentiated, so the price competition is more intense. The increase in the price that customers are willing to pay if an ingredient tastes better than the competitors’ may be small if price is the main dimension of competition. The slightly higher price may not justify the per-unit cost of the additives. In contrast, for processed foods the margin may respond greatly to taste, motivating manipulation of the ingredients.

The taste of the final dish is likely to respond less to manipulating one ingredient than to altering the composition of the entire food, both because the ingredient may be only a small part of the final dish and because the taste of a dish is largely determined by the seasoning and the cooking method. In this case, additives to ingredients do not improve taste that much, reducing the profitability of manipulating these.

Intense price competition motivates cost-cutting, including by substituting cheaper ingredients or using additives (e.g. preservatives) that reduce the manufacturing cost. However, if the additives cost more than they save on production cost (such as preservatives for dry goods that already keep indefinitely), then they are unprofitable to include.

Demand for cooking ingredients may also respond less to price and taste than for restaurant meals or delivered food (raw ingredients may even be an inferior good, but eating out is more like a luxury good). In this case, there is a range of fixed costs of unhealthy substances for which adding these to ingredients is unprofitable, but to processed foods profitable.

Eggs boiled in an oatmeal cooker

In addition to rice cookers, multi-cookers and egg boilers, there are devices specifically for cooking oatmeal, even though a rice cooker would do the job just fine. Perhaps the reason is that the minimal cooking time is shorter for oatmeal than for rice, so an oatmeal cooker speeds up the process compared to a non-programmable rice cooker. A programmable one could of course be set for the shorter cooking time.

The normal cycle length of rice cookers (30-45 min) and oatmeal cookers (20 min) is longer than the 12-15 minutes it takes to hard-boil eggs. However, overcooking a hard-boiled egg does not worsen its taste or texture significantly in my opinion, unlike for meat or vegetables. It turns out that oatmeal does not stick to eggshells that much, so eggs boiled in a cooker together with the oatmeal can be rinsed off quite easily.

Boiling the eggs and oatmeal together saves either time (if there is only one device available for cooking) or the labour of washing one more cooker (when using separate ones for eggs and oatmeal). Even with a dishwasher, disassembling a cooker, putting it in and taking it out of the washer and reassembling takes a few minutes. Rinsing the eggs is quicker.

Food security is a manipulative term

Food security is a manipulative political code phrase designed to scare people and thereby make them support agricultural subsidies, as I have written before. The fear is created by association with sieges before the age of gunpowder, where castles were starved into submission. In modern times, no enemy is silly enough to try to surround and starve a country that is not a city state (e.g. Singapore), because any enemy with a large enough force to prevent food from getting into a country is also strong enough to conquer it quickly by frontal attack. Even unintentional starvation is a public relations disaster (e.g. Yemen), as is a war that drags on, but a quick takeover without too many casualties (e.g. Crimea) actually increases the conqueror’s leader’s popularity in internal politics.

Even if an enemy was stupid and tried to starve a country, the defense against this is not farm subsidies, but many distributed small stockpiles of food. Farms as a food supply are easy to destroy by firebombing the crops and livestock from the air. A small number of large centralised stockpiles are also vulnerable. However, if each household is obliged to keep n months’ worth of non-perishable food at home, then starving the country into submission would take at least n months and bombardment would not shorten that period.

What is really meant by food security is that food prices might rise. However, in all except the very poorest countries in the world, food is so cheap that any reasonable price rise would not cause starvation. For example, according to the USDA, 9 medium baked potatoes fulfill all the nutritional needs of an adult. Similarly, people can survive for a long time eating just wheat flour and water. Wheat flour is 80 cents per kilo, and a kilo of it has 3600 kcal, which is enough for an adult for two days. The price of flour would have to rise at least a hundred times for the cost to lead to starvation in developed countries. Other emergency foods that do not go bad and can be prepared without heating are also cheap, e.g. milk powder, instant oatmeal, canned meats and vegetables.

A price rise is a financial problem, not not a real resource constraint, and as such has a financial solution – insurance. Those afraid of a price rise can use forward contracts to lock in the price. Insurance against a very low-probability event like food prices rising a hundred times is cheap (if such insurance is offered, which it might not be due to the low demand).

Stockpiling emergency food

Sometimes the media scares people into stockpiling emergency food, such as by predicting a snowstorm (or more poetically, snowpocalypse), flood, hurricane or blockade. Even if the threat of being cut off from food and other supplies was real, so stockpiling would make sense, fear often makes people act irrationally: panicking stockpilers buy the wrong quantities of the wrong products, for example dozens of toilet paper rolls and disinfectant wipe packs.

The smart way to prepare for an emergency is to list the products needed (and only those) and then calculate the necessary quantities. For example, medical handbooks such as UpToDate specify the daily nutrient need for a person conditional on age, weight and physical activity. The quantities of foods that satisfy the nutrient need can be found for example using the USDA food composition database. To find the quantity to buy for emergency preparedness, multiply the total daily food intake of the people in the household by the likely duration of the emergency (plus a reasonable safety margin). Tallying supplies is just like planning event catering or consumables for a hike: the number of eaters times the number of meals. The same simple spreadsheet-based quantity calculation applies to other emergency supplies like matches, batteries, medicine, fuel.

A natural disaster may cause power outages and less frequently a loss of water supply. Therefore emergency food should not need cooking and there should be a drinking water stockpile in the home. Contrary to this common sense, irrational emergency shoppers sometimes buy instant noodles, rice and other foods that require hot water to prepare.

Of course, the stockpile of supplies for a disaster should keep for a long time. A minor and neglected aspect of emergency food is that it should not tempt the stockpiler to eat it at non-emergency times. The temptation of course depends on the person, but chocolate bars may be a bad idea, especially in a household with children or binge eaters.

The requirements of being non-perishable, edible without cooking and non-tempting are satisfied by for example canned food, milk powder, instant oatmeal, flour (despite being usually consumed cooked, flour and oatmeal are edible straight from the pack, in contrast to rice, dry peas, beans and cornmeal).

A minor consideration is variety in the food, which helps keep boredom at bay while waiting for a disaster to end.

Ways in which an eater can get negative calories from food

There are at least four ways in which an eater may have less energy and nutrients after consuming a food: mechanical, chemical, physical and biological. The mechanical way is that chewing and other parts of digestion take energy, so if a food requires serious mastication and contains few calories, then more energy may be spent than absorbed. This has been claimed for raw celery.
Chemically, one food may react with another in a way that makes one or both of them less digestible. The less effective absorption reduces the nutrients obtained compared to not eating the second reactant. The chemical pathway to inefficient digestion may have multiple steps. For example, ascorbic acid leaches calcium from the body, and calcium is required for the absorption of vitamin D, so eating more citrus fruits may indirectly reduce one’s vitamin D levels.
When calculating the calorie content of food, indigestible fibre is subtracted from carbohydrates before adding up the energy obtained from carbohydrates, fats and proteins. However, if fibre reduces the absorption of calories (in addition to its known reduction of the absorption iron, zinc, magnesium, calcium and phosphorus), then the food’s bioavailable calorie content is less than that obtained by simply subtracting the fibre. To derive the correct calorie content, the fibre should then have negative weight in the calculation, not zero. This difference may explain why in Western countries, a high-fibre diet predicts better health in multiple dimensions in large prospective studies (Nurses’ Health Study, Framingham Heart Study), controlling for calorie intake, lifestyle and many other factors. If the calorie absorption is overestimated for people eating lots of fibre (because the calorie intake is larger than the absorption), then their predicted health based on the too high calorie estimate is worse than their actual health. This is because most people in Western countries overeat, so eating less improves health outcomes. If the predicted health is underestimated, then the high-fibre group looks unusually healthy, which is attributed to the beneficial effects of fibre, but may actually be due to absorbing fewer calories.
A food may chemically break down tissues, e.g. bromelain and papain, from fresh pineapple and papaya respectively, denature meat proteins, so cause mouth sores. Rebuilding the damaged tissue requires the energy and nutrients, the quantity of which may exceed that absorbed from the food.
Chemically causing diarrhea reduces the time that foods (including the laxative agent) spend in the gut, thus reduces nutrient absorption.
Stimulants like caffeine speed up metabolism and cause greater energy expenditure, but may give zero calories themselves, resulting in a net negative caloric balance.
Just like chemical damage, physical injury to the body necessitates spending calories and nutrients for tissue repair. For example, scratchy food (phytoliths, bran) may cause many microscopic wounds to the digestive tract.
Cold food requires the body to spend energy on heating, so if the calorie content is small, then the net energy obtained is is negative. Examples are ice cubes and cold water.
A food substance may physically partially block the absorption of another, for example a gelling agent (methylcellulose, psyllium husks) may turn a juice into a gel in the gut and thereby reduce its absorption. Based on my personal experience, psyllium husks gel liquid feces, thus effectively reducing diarrhea. Mixing psyllium husks with carrot juice and with asparagus powder dissolved in water before consuming them during the same meal results in the excretion of separated faint orange and green gels somewhat distinct from the rest of the feces (photos available upon request, not posted to keep the blog family-friendly). This is suggestive evidence that the gelling agent both kept the juices from mixing in the gut and reduced the absorption of the colourful compounds by keeping the juice in the centre of the gel away from the intestinal wall.
Biologically, a food may reduce the nutrients available to the organism by causing infection, the immune response to which requires energy and depletes the body’s reserves of various substances. Infection may lead to diarrhea, although the mechanism is chemical, namely the toxins excreted by the microbes. Infection with helminths (intestinal worms) that suck blood through the wall of the gut requires the replenishment of blood cells, which uses up calories, protein and iron.
If the food takes a long time to chew or is bulky, then chemical and electrical signals of satiation are sent from the gastrointestinal tract to the the appetite centre of the brain. These signals reduce the desire to eat, thus decrease calorie intake.