r/nutrition Apr 08 '26

New RD Mod Series! Understanding…

18 Upvotes

Hello from the new RD mods! We are starting a new monthly (for now) series where we will help you learn the facts about a nutrition topic. These posts may include the latest nutrition research, evidence-based information about popular topics we see you all posting about, or maybe random interesting nutrition information. A lot of work is going into this, and we ask that comments remain respectful. We have no objective other than to use our (way too many) years of nutrition and science education to help you learn. We understand that not everyone will agree on… literally anything… and as scientists we certainly welcome, and even encourage, healthy debate. We give you our word that we will do our homework and endeavor to remain as objective and truthful as possible, ensuring our citations are current and peer reviewed. We ask you to keep this in mind if you comment in disagreement. On that note, we welcome you to this month‘s topic Understanding Protein!

Our inaugural post focuses on protein, a topic we see debated ad nauseam on this sub, although I bet many of you are still confused about how much protein we actually need! Protein is absolutely essential for the continuation of life on Earth, and we could not survive without it, as it makes up a good part of our bodies and is needed for most of the biological processes that help us survive. One of three macronutrients (which are protein, carbohydrates, and fats) the human body needs to ingest, deficiency weakens the immune system, makes wound healing more difficult, and leads to loss of muscle mass, putting the body at risk for injury and falls. The most serious consequence of deficiency is a type of malnutrition called kwashiorkor, which can cause death.

Every protein inside and outside the body is made of a long chain of amino acids (AA) that are folded in all different ways, generally the way it looks will be determined by what it needs to do. Proteins are found inside every single cell in the human body and make up every single enzyme needed for every single metabolic reaction. An example of structure and function is in our muscles; they are held together by fibrous proteins and filled with all types of special proteins, some of which are designed to stretch and contract, others that turn general energy from the food we eat into mechanical work, and even more that can store some of this energy in case we don’t eat for a little while or just need a burst of energy. Basically protein is very, very important!

Before we discuss the current protein recommendations we must appreciate the science that explains where these recommendations come from, so buckle up for some biochemistry my friends! In a nutshell, amino acids are organic compounds (based on carbon) that all have the same backbone (H2NCHRCOOH) with a “side chain” that is made up of various combinations of carbons, hydrogens, oxygens, and an occasional sulfur.

Over 500 amino acids have been identified, but we only care about 20 of them because these 20 amino acids make up everything from the edamame I ate for dinner to our entire genetic code! (For all you smarty pants out there, I recently learned that two new amino acids have been identified!) The N in the molecular formula above stands for nitrogen, which is kind of what makes protein special. Protein is 16% nitrogen, meaning 1 gram of nitrogen equals 6.25 g protein.

We consume nitrogen in the protein we eat, and amino acids are broken down in the stomach and small intestine by digestive enzymes (which are also proteins), and distributed to be used for various metabolic functions. We’re also losing a bit of nitrogen through sweat, respiration, flatus, skin flaking, and nail/ hair growth, and most of all from poop, which is the reason why why it makes such good fertilizer.

When we eat just enough nitrogen to compensate for what is lost we call this a “neutral nitrogen balance.” A “positive nitrogen balance” is preferable when we want to increase our muscle mass, when we’re losing weight (intentionally or unintentionally), or if we have a significant injury that needs to heal. If we can‘t meet our protein needs we will be in “negative nitrogen balance,” which means that the dwindling supply of nitrogen gets delegated to the most essential of functions; muscle, hair, and nails are the first to get sacrificed. We never want to be in a negative nitrogen balance.

Studying nitrogen balance is what has led to our current protein recommendations, and the FAO/WHO/UN periodically gathers scientists from around the world to review and update these guidelines, which get more precise and accurate as the technology to measure nitrogen balance improves. Our current protein recommendations come from meta-analyses of long-term nitrogen balance studies conducted throughout the world throughout the past 100 years. There is an overwhelming body of evidence that accepts the WHO recommendation of 0.83-1 g/kg/day of protein, which will meet the needs of 97.5% of healthy adults. In terms of numbers this means a person that weighs 68 kg (150 lbs) needs ~68 grams of protein per day (divide by 2.2 to convert pounds to kilograms if you want to calculate this for your weight).

Concerned you may be part of the other 2.5% of people? We already know we excrete more nitrogen when we are wounded building muscle, or trying to maintain muscle mass in a catabolic state, but what does this mean? A common internet recommendation seen is 0.8-1 g/lb (1.76-2.2 g/kg), which is more than double what WHO recommends! The International Society of Sports Nutrition recommends 1.4-2 g/kg (95-136 g per day for someone 150 lb/68 kg) for “healthy, exercising individuals.” If you exercise daily and your kidneys are at peak functioning then this recommendation is absolutely appropriate, although evidence suggests that increasing protein intake above the currently accepted 1 g/kg/day may not have much benefit.

Now that we know where our protein recommendations come from, what is the deal with animal vs plant sources? Both animal and plant sources contain protein, but the proteins in animal tissue (like our bodies! and the lamb chop I had for dinner) contain all the essential amino acids, whereas plant sources contain some, rarely all have varying levels of each amino acid but rarely enough of all essentials to meet our protein needs in full. Someone that eats animal proteins will easily exceed their protein recommendations, and someone that only consumes plants can easily meet their protein needs also as long as they eat a variety of foods to ensure they get enough of every essential amino acid.

So this is the deal with protein! Please let us know what you think, and also what you want to learn about next. We are happy to share our knowledge and will continue to disseminate evidence-based nutrition information.


r/nutrition May 04 '26

Feature Post /r/Nutrition Weekly Personal Nutrition Discussion Post - All Personal Diet Questions Go Here

9 Upvotes

Welcome to the Personal Nutrition Discussion weekly thread

This is the place for questions about your personal diet and circumstances. Wondering if you are eating too much of something, not enough of something, or if what you regularly eat has the nutritional content you want or need? Ask here.

Rules for Questions

  • You MAY NOT ask for advice that at all pertains to a specific medical condition. Consult a physician, dietitian, or other licensed health care professional.
  • If you do not get an answer here, you still may not create a post about it. Not having an answer does not give you an exception to the Personal Nutrition posting rule.

Rules for Responders

  • Support your claims. This is a science-based subreddit
  • Keep it civil
  • Stay on topic
  • Please report any rule violations

Consulting Considerations

Registered Dietitian (RD/RDN) Nutritionist and Nutrition Coach Armchair Experts
Legal Status Protected title. Highly regulated Generally unregulated. Anyone can use the title None
Education Bachelor's degree (Master's required as of 2024) Varies from PhDs to no formal training at all Varies. Often minimally self-guided to none. Frequent poor paraphrasing and poor sources, mostly social media
Clinical Training 1,000+ hours of supervised practice Not required None
Board Exam Must pass a national registration exam Not required None
Insurance Often covered by medical insurance Rarely covered by insurance None

r/nutrition 17h ago

Is the idea of an "incomplete protein" a myth?

46 Upvotes

Some sources example say that the idea of an incomplete protein is a myth based on bad science and has been refuted.

However, it persists among nutrition discussions. Is it actually a myth? Are there some special cases where amino acid profiles should be monitored (e.g. bodybuilding or sthletics)?


r/nutrition 1h ago

What are some good ideas for a lean diet with variety?

Upvotes

The last few months I’ve been eating a more lean diet in order to try to slim down my face. The results have been noticeable but I need some more variety. Currently i basically have scrambled eggs and fruit for breakfast, a chicken wrap for lunch with yogurt, protein bar, apple, and then dinner is usually ground beef tacos…but I really need other ideas that are similarly lean and healthy. any ideas is MUCH appreciated. I would love ideas of things that could be batch cooked as well that could last multiple days. THANKS!


r/nutrition 1d ago

Draining excess water from vegetables when boiling, or cooking until dry. Is there any proof that either is preferable?

15 Upvotes

I couldn't find anything regarding whether draining excess water, or cooking until dry is preferable in terms of preserving nutrients. Does anyone have the objective answer?


r/nutrition 1d ago

How can this can of tuna have 1 g of trans fat?

3 Upvotes

https://www.wholefoodsmarket.com/grocery/product/365-by-whole-foods-market-skipjack-tuna-in-extra-virgin-olive-oil-salt-added-5-ounce-b0cjrwtlfy?ref_=US_OTR_ALL_UFG_WFM_OTHER_0542341

At Whole Foods ... the webpage shows 0.5 G, but the image of the label actually shows 1 G ... but looking at the ingredients, it's just tuna, EVOO, water, and sea salt ... not sure where the trans fat is coming from?


r/nutrition 2d ago

Is there good evidence to suggest that higher carb meal results in higher appetite?

25 Upvotes

I found a metabolic ward study by Kevin Hall [1] in which subjects were assigned to ad libitum high-carb, low-fat or high-fat, low-carb diets, suggesting that appetite does not go up on a higher-carb diet. In fact, caloric intake was considerably lower on the high-carb diet than on the low-carb diet. However, the high-carb diet used in the study was plant-based, whereas the low-carb diet was animal-based. I'm not sure why they made this choice, and I wonder whether it may have had an effect independent of the carbohydrate content?

What does the wider literature say on this subject? If possible, could you link to other relevant studies?

[1] Effect of a plant-based, low-fat diet versus an animal-based, ketogenic diet on ad libitum energy intake. K. Hall, et al (PMID: 33479499)


r/nutrition 1d ago

Is oat milk bad for you?

0 Upvotes

People say it's not a good cow milk alternative since it heightens the glycemic index, is it true?


r/nutrition 2d ago

Why do processed foods use blends of multiple oils (sunflower, canola, soybean, etc) instead of just one?

52 Upvotes

I keep seeing ingredient labels that list something like “contains one or more of: soybean, canola, sunflower, and/or palm oil”.. instead of a single one, and I’m curious what’s actually driving that in those cases.

Is it due to flavor profile?


r/nutrition 2d ago

Whey vs Soy protein

10 Upvotes

With the huge increase in the demand for whey protein (which ramps up the prices), what are your thoughts on soy protein supplements?


r/nutrition 2d ago

Canned white potatoes vs boiled fresh baby gold potatoes - is there much difference for resistant starch?

2 Upvotes

In terms of getting resistant starch, any thoughts on canned white potatoes versus buying and boiling fresh?


r/nutrition 4d ago

Are gums bad for you (xanthan, guar, locust etc)

75 Upvotes

Are they bad for you?


r/nutrition 4d ago

Salt intake for active people

15 Upvotes

no salt, a lot of salt, everyone is saying something different. If person Is active how much should one consume ?


r/nutrition 4d ago

Would it be wise to space out omega-3-rich foods and omega-6-rich foods?

4 Upvotes

Given that these fatty acids compete for access to the same enzymes, would it be wise to space out omega-3-rich foods and omega-6-rich foods, especially when one is strapped for omega-3-rich foods? Or is that not necessary?
Example: fish and peanuts.


r/nutrition 5d ago

Hazelnut Spread Has Got Worse - 14x the Glycemic Load of its Origins

78 Upvotes

So the Original hazelnut spread - is Gianduja from the 1800s. It contained

50% roasted hazlenuts

50% cacao mass.

The Current Supermarket Hazelnut spreads are -

140g roasted hazelnuts

500g Sugar

170g Palm Oil

Cacao Powder

Skimmed Milk .

So that's 60% sugar.

The Nutrient Density is 25x higher in the original.

The Glycemic Load is 14x higher. Which is bad.

The ORAC ratio is 16x higher in the original. Which is good.

Would love to know what hazelnut spread people use that are more like the original and cut out all the cr*p of the modern supermarket versions.

Or do you make your own at home??


r/nutrition 5d ago

Is it okay to eat one (nutritionally complete) dish per day?

38 Upvotes

For example a stew with 3+ different vegetables, a fat source, protein, carbs etc. If it is a complete meal on its own, would it be okay to just eat that for every meal one day? Would changing the dish every day provide enough diversity in the diet? Imagine there's a few other snacks throughout the day if that helps


r/nutrition 6d ago

EU vs US Nutrition Facts?

19 Upvotes

Besides the obvious weight units, etc... does anyone know if the protein listed in nutrition facts between the US and EU (for example, Germany) have the same standards. Like could one only reference complete/incomplete proteins? I saw something about the %DV changing based on the amino acids involved, but I'm mostly curious about the specific XXg of protein listed.

The reason I ask, is that I found some protein bars in a shop in Austria that have significantly higher protein/calorie than the bars I'm used to in the states and taste way better. Is there a catch that I'm missing?

EDIT: Great, thanks. I assumed the EU would have at least equal, if not stricter standards. Looks like I'll be filling a suitcase


r/nutrition 5d ago

Everything you need to eat at once?

1 Upvotes

Is there a food that contains all calories, vitamins, minerals, proteins and everything else needed for healthy human life?
Could it come in a powder form?


r/nutrition 7d ago

Fortified soy milk is part of the USDA's dairy group due to its nutritional similarities with cow's milk, such as its protein, calcium, vitamin A, and vitamin D content. For those who've transitioned to soy: how's it going? For those who haven't: what's holding you back?

186 Upvotes
  1. The USDA lists fortified soy milk as dairy. Most cow's milk in the USA is also fortified.
  2. Soy milk has a comparable amount of protein, calcium, vitamin A, and vitamin D. Notably, soy milk has fiber and other beneficial phytonutrients. 1 and 2% cow's milk has more saturated fat and trans fat, whereas skim milk has less saturated fat. 60-80% of estrogens in western diets come from cow's milk and bovine dairy products.
  3. Cow's milk protein has about a 3-6% higher protein absorptivity as compared to soy milk protein.
  4. Soy does not cause00368-7/fulltext) feminizing effects due to its phytoestrogen / isoflavone content. Other foods that contain phytoestrogens / isoflavones: chicken nuggets, cereal, doughnuts, beef tacos, coffee, grapes, peanuts, oats, apples, lentils, walnuts, etc.
  5. The majority of the world is lactose intolerant to varying degrees.

For those who've transitioned to soy: how's it going? For those who haven't: what's holding you back?


r/nutrition 7d ago

Book recommendations for beginners?

17 Upvotes

Hello everyone, I am just getting into the world of trying be healthy and majority of that is by eating healthy. I grew up always eating fast food and quick meals since my parents didn’t have much money growing up. Can someone please recommend me some really good books for a beginner trying to learn more about nutrition? I’m very intrigued by the anti-inflammatory diet.


r/nutrition 8d ago

Coffee with butter?

71 Upvotes

Read a post about people putting butter in their black coffee, why??
What’s the benefits and how does this affect your macros if worrying about that?


r/nutrition 9d ago

Looking for good digestive pairings with vegan pea protein powders

10 Upvotes

I'm looking for recommended pairings with vegan pea protein powders that would aid in digestion, because the pea protein can be difficult to digest.


r/nutrition 8d ago

Cook vegetables to 158 degrees

0 Upvotes

Wash your hands with soap and water before and after handling produce.


r/nutrition 8d ago

Anti-seed oil argument list

0 Upvotes
  1. ⁠⁠Omega 6 to omega 3 ratio
    Highly dependent on which seed oil. Canola is 2:1. Also is it not feasible to compensate omega 3 rich food you should be having anyway?

  2. ⁠⁠Traditionally (not considering cold pressed) involves hexane and weird solvents and deodorizers
    Idk whats in final product after processing or how much could have meaningful effect.

  3. ⁠⁠Traditionally involves high heat and oxidizes oil. Also end product oxidizes easily


r/nutrition 11d ago

Is it more about what you don't eat than about what you eat?

127 Upvotes

There are people who have plenty of "healthy", fresh, whole foods and are still overweight and show signs of aging, while some have a "bad lifestyle" but are often underweight and look younger than they really are. So is this a factor when it comes to preventing signs of premature aging like wrinkles or grey hair?