One of my favorite things about the Power Smoothie is that it makes it easier to eat ethically. This page elaborates on that statement.

My sense is that factory farms do a great deal of damage to the world that isn’t included in the prices of their products. This includes environmental impact and cruelty to animals. I know very little about the former; what I know about the latter mostly comes from a book by Peter Singer (note that Prof. Singer promotes the organization I co-founded, GiveWell). If you prefer a 10-minute video, here’s a really horrifying one. While environmental impacts could come from both animal and plant foods, my sense is that animal foods generally involve a lot more waste and environmental impact (I have no citation for this though).

So I would like to avoid factory-farmed animal products. Unfortunately, it is really hard to reliably and conveniently find non-factory-farmed animal products. Many reassuring-sounding labels, such as “humanely raised” and “grass fed,” mean very little. Even the more hard-core labels such as Certified Humane don’t seem to me to mean as much as I want them to mean: for example, Petaluma Farms and Pete & Gerry’s are both Certified Humane, yet Prof. Singer’s book includes a very disturbing-sounding visit to Pete & Gerry’s, and Petaluma Farms was kicked out of an SF Farmers’ Market for not meeting its higher standards. There are producers and sources I trust, but it’s a lot of hassle to investigate them and to consistently get my food from them.

Given this situation, many people advocate being vegan. However, many people – including myself – have a lot of trouble feeling satisfied with vegan meals, particularly with vegan meals that are easy to purchase or prepare. Generally, I need a lot of protein and fat to feel satisfied. My interest in Power Smoothie has largely been driven by this dilemma: trying to find a way to regularly and easily get the protein and fat I need while consuming minimal animal products.

The vast majority of Power Smoothie ingredients come from plants. The potential exception is whey protein powder. There is no need to use whey protein powder in a Power Smoothie; there is a Vegan powder that I recommend. However, the whey protein is cheaper, easier to blend, less noticeable flavor-wise, and (according to me, at least) more satisfying, so it’s worth briefly addressing the ethical implications of using whey protein powder:

• I find this article eye-opening and useful. It argues that poultry and eggs require far more “animal lives per calorie” than pork and beef, and that the impact of dairy is extremely small in comparison to all of these things. (I haven’t vetted these figures, but they seem like the sort of figures that should be easy to obtain fairly accurate versions of, and I know the author and would guess these figures are ballpark-fine.) Basically, one cow provides a lot of milk: 17,640,000 calories over the course of its life (6000x as much as a broiler chicken).
• I don’t know exactly what the story is with whey protein, but since whey protein comes from milk, I can make an educated guess. According to this LiveStrong page (consistent with other sources I’ve checked), 1 cup of low-fat milk contains 8.53 grams of protein, of which 18% is whey protein, implying that 1 cup of milk contains ~1.54g whey protein. So to get 25g of whey protein (the recommended dose for a standard Power Smoothie) would require about 16 cups of milk (25/1.54), or about 2000 calories at 124 calories per cup. That means that if a cow produces 17,640,000 calories’ worth of milk over the course of its life, it produces the equivalent of ~8700 scoops of whey protein powder, assuming that the protein is isolated perfectly. This would imply that having one Power Smoothie a day for 24 years would account for one cow.
• While this estimate does assume perfect isolation of protein, it’s also worth noting that whey is a by-product of cheese production, i.e., the other parts of the milk are used too and may actually be in more demand than the parts used to make whey protein powder. Thus, I think this estimate is more likely to overstate than understate the impact of whey protein powder consumption, and overall I’d be surprised if anyone could consume enough Power Smoothie in their lifetime to account for 2 cows (at a few Power Smoothies a week currently, I doubt that I will account for 1). Contrast this with chicken, in which it might only take 3-4 chicken-heavy meals to account for one chicken’s life.

Overall, I personally believe whey protein’s problematic ethical impact is small enough to be outweighed by the benefits of using it. If you disagree, you’re probably a fairly absolutist vegan, and in that case I recommend using vegan protein powder.

The bottom line is that Power Smoothie – regardless of the variant – provides a level of protein and fat that is very hard to obtain with such a small amount of impact on demand for factory-farmed animals. For people who need protein and fat to get satisfaction from their meals, this makes it a valuable tool in eating ethically.

Update: a friend of a friend claims that the above calculation overstates the amount of “calories per cow” because “Generally, a calf is killed every time a cow goes through a lactation cycle (need babies to produce milk!). In some cases female calves are saved and used for milk production, so at best every second calf would be killed (males) – although a rough estimate would place female retention at more like every ten or so.” This would make the above calculation off by 2.5-5x (in the direction we don’t want – it would imply that it takes less Power Smoothie consumption to account for one cow). I haven’t updated the above calculation because I don’t yet have a source for this claim, but at some point I may look for one and try to nail this down better. I would still guess that whey is primarily a by-product, making this something of a moot point.

Update 2: some further updates in favor of Power Smoothie having very little impact on animal suffering, via Lewis Bollard (I haven’t vetted these claims myself; emphasis mine):

You should change from comparing “calories per life,” which is hugely skewed by lifespans — 4-6 years for a dairy cow vs. 35-55 days for a broiler chicken — to “calories per day.” (Assuming you agree with me that suffering, not lives lost, is what matters.) For dairy cows, that would be about 15,000 calories/day (avg. 6.5 gallons of milk/cow/day * 8.5lbs per gallon * 272 calories per lb of whole milk — these are conservative numbers; some stats put gallons/day higher). (3) Given that whey seems to be either as in demand, or less in demand than, other parts of the milk, it seems to make sense to just count the calories of the whey (assuming the other calories in the milk will be used for cheese etc.). (Note these numbers assume that the whey protein concentrate provides the same average value per calorie to producers as other components of milk. I haven’t found great numbers breaking down the relative value of cheese and whey sales to cheese producers, who produce whey as a byproduct. But within the whey market, the prices for “Dry Whey Central” (used for humans) and “Dry Whey Animal Feed” are surprisingly similar. This suggests that human use whey protein is not disproportionately profitable to dairy producers, though that could change if demand surged since whey protein concentrate supply is limited by the inefficient process used to produce it.) The power smoothie requires 25g of whey protein, which is 100 calories (just from the protein — presumably they soup it up with fat and sugar from non-dairy sources, so not counting those). That implies each power smoothie contributes to just 1/150th of a cow’s daily milk output. I.e. if you have a power smoothie every day for a year, you’ll only be responsible for 2.4 days of a cow’s life on the farm, and if you have a smoothie every day for the next 30 years, you’ll only be responsible for 70 days of a cow’s life.  (4) If the contribution to demand is really this low, I think the other aspects of the dairy industry are pretty irrelevant. My understanding is that the average dairy cow is kept for about 3.6 births, and the replacement rate is just over 1 because mortality is low, so perhaps 2.5 calves are killed near birth per cow over its 4-6 year commercial lifespan. So if you drank power smoothies every day for 30 years, you’d only be responsible for about 1/10th of a calf getting killed. Hope this is all good news!