Answering a dietitian's negative feedback


You are not being pedantic you are being stubborn. So your point is that Soylent has more than the recommended 35% of calories from fat. Like I said before NO DUH. You have to look at why that is the recommendation and read studies on fat intakes and their effects on health.

These ranges are associated with reduced risk of chronic diseases, such as cardiovascular disease, while providing for adequate intake of essential nutrients.

A strong body of evidence indicates that higher intake of most dietary saturated fatty acids is associated with higher levels of blood total cholesterol and low-density lipoprotein (LDL) cholesterol. Higher total and LDL cholesterol levels are risk factors for cardiovascular disease.

A number of studies have observed an association between increased trans fatty acid intake and increased risk of cardiovascular disease. This increased risk is due, in part, to its LDL cholesterol- raising effect.

From the results:

The HFLC group had greater mean decreases in serum triglyceride (P=0.07), and hs-CRP (P=0.03), and greater mean increases in HDL cholesterol (P=0.004), and total adiponectin (P=0.045) relative to the LFHC.

Several studies indicated an increase of HDL-cholesterol and a corresponding decrease in triacylglycerols following a MUFA-rich diet. The effects on total and LDL-cholesterol appeared not consistent, but no detrimental effects on blood lipids were observed. Values for systolic and diastolic blood pressure were found to be reduced both during short- and long-term protocols using high amounts of MUFA as compared to low-MUFA diets.

Data from meta-analyses exploring evidence from long-term prospective cohort studies provide ambiguous results with respect to the effects of MUFA on risk of coronary heart disease (CHD). One meta-analysis reported an increase in CHD events, however, most meta-analyses observed a lesser number of cases in participants subjected to a high-MUFA protocol. Although no detrimental side effects of MUFA-rich diets were reported in the literature, there still is no unanimous rationale for MUFA recommendations in a therapeutic regimen.

LDL cholesterol is affected by diet. Knowing which fats raise LDL cholesterol and which ones don’t is the first step in lowering your risk of heart disease and stroke. Your body naturally produces LDL cholesterol. Eating saturated fat,and trans fat raises your blood cholesterol level even further.

For adults who would benefit from lowering their LDL cholesterol, the American Heart Association recommends:

Reducing saturated fat to no more than 5 to 6 percent of total calories. For someone eating 2,000 calories a day that’s about 11 to 13 grams of saturated fat.

Reducing the percent of calories from trans fat.

The American Heart Association’s Nutrition Committee strongly advises these fat guidelines for healthy Americans over age 2:

Eating between 25 and 35 percent of your total daily calories as fats from foods like fish, nuts, and vegetable oils.

Limiting the amount of saturated fats you eat to less than 7 percent of your total daily calories. That means if you need about 2,000 calories a day, less than 140 calories (or 16 grams) should come from saturated fats.

Limiting the amount of trans fats to less than 1 percent of your total daily calories. That means if you need about 2,000 calories a day, less than 20 calories (or 2 grams) should come from trans fats.

For good health, the majority of fats you eat should be monounsaturated or polyunsaturated.

Visit our Fats 101 page to learn more about these fats.

It’s easier to gauge how much healthy and unhealthy food you are eating by using a food diary to keep track of what you eat for a period of time.

Soylent 2.0 has 2g of saturated fat per serving. 2g/serving x 5 servings/day = 10g/day

Soylent 1.5 has 2.5g of saturated fat per serving. 2.5g/serving x 4 servings/day = 10g/day
Soylent 1.5 also has less than 0.5g of trans fat per serving. >0.5/serving x 4 serving/day = >2g/day


To add to @horsfield, I went through the dietary guidelines and searched for “fat” in the document. In almost every instance, the paper is only interested in recommending the minimization of saturated (alternatively “solid”) fats. Unsaturated fats (alternatively “oils”) are praised aside from their high caloric density. So, as long you as you are being careful with total caloric intake and avoiding trans fats, there seems to be no reason to be concerned by consumption of unsaturated fats in the recommendations.


You see the words “strongly advises” and make conclusions like, “all else forbidden.”

They are advising a range, not specifying a cap. They are advising the range 25%-35% for people eating typical foods for a reason - and this is a direct quote

That is the express purpose of their guidelines.

Incidentally - the line with the 25%-35% range you keep referring to refers, in context, to eating between " 25 and 35 percent of your total daily calories as fats from foods like fish, nuts, and vegetable oils." Since you apparently believe that means all else is forbidden, do you believe that they are forbidding all consumption of beef, cheese, eggs? Clearly, no, they’re just advising a focus, not excluding all else. Yet you won’t interpret the other half of the sentence the same way.

Lastly, but very importantly, about this:

To present text I did not write as if it were directly quoting me is intellectually dishonest as well as fraudulent.


Hello internet stranger! If you were passing by, checking out the forums and happened to wander into this thread first, do not be dismayed.

If you are like me, then you also get horrifying dizziness when you are bombarded with too many numbers and graphs too quickly. Before you turn away, having subjected your brain to the kind of mental flatulence you’d get from a cup of ol’ Soylent 1.0, rest assured there are other less intense threads that are free of P values and bar charts and percentages of fractions of decimals. Take a break, take a breath, come back and digest this all when you’re feeling better.

I’ve included a therapeutic aid to speed this process along. Enjoy the sounds of waves and soothing wildlife rustling about. Let a warm calming glow fill your being until you are at peace with life, the universe and everything.

Then whip out a calculator, open 20 tabs and tear the world of research a new rear end. Kthxbai.


Here is a TED talk from someone doing actual clinical research on real humans on the topic of high fat diets.

The micronutrient claim is questionable for two reasons: First, oat flour, and anything else that comes from natural sources, is going to have micronutrients. More importantly, unless you are mixing your Soylent using exclusively distilled or reverse osmosis purified water, you will get your micronutrients just from the water. And even if you do use distilled water to mix your Soylent, if you are drinking any other water during the day that is not distilled, you will get your micronutrients from that. In short, for micronutrients to be an issue, Soylent would have to remove the oat flour and you would have to consume exclusively distilled water, and you would have to not ever eat anything except Soylent.

If you read through some of the blog posts and various other questions, you will find that the micronutrient thing was very carefully considered, and that it was established that drinking non-distilled water would cover them. Rob also suggests periodically eat real food, for social reasons and to cover anything that Soylent does not contain that we may not know that humans need, because that is a more serious concern than micronutrients.

As others have said, there is no upper limit for fat consumption. There are guidelines for certain kinds of fat, and Soylent is careful to stay within those. There are also recommendations for consumption of fats for which the profile is not well known, designed to help people stay within the guidelines on saturated and trans fats. There is no upper limit for fats in general though. In addition to all of that, keep in mind that our understanding of nutrition is still pretty limited. Until recently, sugars were regarded as completely safe even in large amounts, except with regards to dental health. The current upper limit for manganese is half what the typical vegan consumes, and there has never been a report of a vegan exhibiting symptoms of manganese poisoning, largely because the IoM does not differentiate between molecules found in natural sources and molecules found in industrial sources. Fat has been demonized since the '60s, but so far there is absolutely no evidence that getting a significant portion of your calories from fat leads to obesity, and in fact, there are a number of high fat diets that are common in some parts of the world where obesity is incredibly uncommon (and not due to malnutrition, either).

Anyhow, watch that TED talk if you have time. The common consensus in nutrition is that high fat intake leads to obesity or other problems, but when fats are limited to healthy fats, the evidence strongly suggests that this is just not true. The claim that high fat intake is bad is just plain not based on sound evidence.


Soylent no longer contains oat flour, they made the switch in 1.8 to soluable corn fiber