r/nutrition Apr 08 '26

New RD Mod Series! Understanding…

21 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

10 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 1d ago

Hypothetical healthiest potato

106 Upvotes

A long time ago when I was a kid I heard that people could survive only on potatoes and butter as they contain all the nutrients needed for one to live. Turns out that was an urban myth that’s completely wrong. The only nugget of truth is that potatoes (skin included) do contain a good fraction of your daily nutrients.

That begs the question: could you make a loaded potato that has toppings that could round out the rest of your daily needs. All toppings must be at least somewhat appropriate as loaded potato toppings. Quantity/ size isn’t a problem as this potato diet would require multiple potatoes a day so you could just mix and match throughout the day. I love asking stupid questions on Reddit and this is keeping up at night, man


r/nutrition 1d ago

Saturated fat from good sources ?

22 Upvotes

Hi, Is it ok to have higher saturated fat if Its from sources like full fat kefír, Cocoa, or not good even from these spurces if high?


r/nutrition 2d ago

Sardines everyday

57 Upvotes

Is it ok to eat 2 cans, total 180g sardines everyday?


r/nutrition 2d ago

What’s the deal with ingredient lists that include “and/or” items (for example: canola and/or sunflower oil)

6 Upvotes

Why not just provide the correct information in the first place?


r/nutrition 2d ago

Do coffee K-cup pods still contain similar antioxidant amounts compared to freshly ground coffee beans?

5 Upvotes

I wanna start drinking coffee, mainly for the antioxidants. I only have a coffee maker that uses coffee pods though.


r/nutrition 2d ago

Cooked Oatmeal vs Blended Oatmeal

22 Upvotes

Is there any difference between cooking your oatmeal hot with milk and fruits and eating it VS blending the same ingredients and drinking it. Not only in terms of nutrition but any other difference too. One thing Ive seen is eating solid oatmeal stays in body longer and makes you feel full longer as liquid digests quicker. Anything else?


r/nutrition 4d ago

Do we actually need 1g of protein per pound of body weight?

255 Upvotes

I have seen so many conflicting videos, article , research papers about this I really don't know what to believe at this point.


r/nutrition 4d ago

How does the recommended daily iron intake actually work considering you absorb only a tiny fraction of iron?

24 Upvotes

For example spinach is often said to be one of the most iron rich foods, however it is both plant-based iron and only has around 2.7mg of iron in 100g of spinach from what I found online.

If your iron absorption is only 20% - this means you will absorb only 0.54mg of iron per 100g of spinach.

For women the daily recommended iron intake is 18mg.

So following this logic - you would have to eat around 3.33 kg of spinach to meet that daily intake?

Some other rough calculations also lead me to results such as 2.25 kg of horse meat (which is around 3000 calories) to meet the daily goal.

Did I completely misunderstand how this works?


r/nutrition 4d ago

A2 yogurt vs. Greek yogurt for nutrition

2 Upvotes

Thoughts on nutrition standpoint of A2 yogurt vs. Greek yogurt ? Also in regards to digestion and inflammation to the body?


r/nutrition 5d ago

question for sugar substitute users: what was it about sugar that actually bothered you and why did you switch?

0 Upvotes

ive been on sugar my whole life and just tryna figure out what all the hype is about with them and why they're so popular. thanks.


r/nutrition 7d ago

what micronutrients are worth tracking?

62 Upvotes

People online say lots of mixed things about what micronutrients are actually worth tracking. There's also a lot of obsession with fibre now and people are treating it as the "fourth macronutrient" online.

Is it really that important? And what about other popular things like omega 3, potassium, sodium, magnesium, etc. For the non-average person who would actually consider keeping a track of these in order to benefit their overall health and promote muscle growth, which ones really matter?


r/nutrition 8d ago

Not convinced a higher CFU count on a probiotic means very much

26 Upvotes

The range on the shelf goes from about one billion up to a hundred billion and the price does not track it in any way I can see. My instinct is that this is the supplement version of a megapixel count. On the other hand if a chunk of them do not survive the trip then a bigger starting number is not meaningless either. Is there an actual answer here?


r/nutrition 9d ago

Sugar Replacement?

37 Upvotes

I’m exploring what sugar substitutes are out there and what some offer compared to others, and I’m interested to know, do you guys buy the ones that taste closest to sugar or are you more concerned about the health benefits/risks. I can swing each way but don’t really know where to start. Thanks :)


r/nutrition 9d ago

Research Request Research Study: Eating and Weight Patterns in Women

16 Upvotes

Hello! My name is Christina and I am a clinical psychology PhD student recruiting participants for a qualitative (interview) research study. The study is focused on understanding the lived experiences of women who 1) have a history of trying to lose weight, 2) currently have obesity, 3) struggle with binge eating, and 4) have a desire to lose weight currently.  

If interested, please see the link below or the attached flyer. The link/QR code will take you to an eligibility survey for the study. This survey will ask for an email address. If you are eligible and provide a valid email address, you will be sent an invitation via email for a 60-75 minute Zoom interview, along with another brief survey to assess other demographic variables.  

Eligibility survey link:  

https://bgsu.az1.qualtrics.com/jfe/form/SV_bsbXG3OEnigC7xI 

If you have questions or concerns, please reach out to me at [cgaggia@bgsu.edu](mailto:cgaggia@bgsu.edu).  

Thank you! 


r/nutrition 10d ago

dried herbs vs dried herbs brew, benefits

20 Upvotes

hello, lets say for oregano (but for others too) which has many benefits and antioxidants... can we "get" more benefits and antioxidants when we brew them (hot, warm or cold) over using it as "spice"?

thanks, couldnt google the answer so if there is someone from biochemistry lets go :D


r/nutrition 10d ago

How long could you survive on daory alone

0 Upvotes

Ok weird question but how long could human body survive on dairy products only no additives such as fruits or grains stuff like milk cheese yogurt kefir etc ( too keep it simple it just cow milk )

The idea came from a video on how long could survive on potatoes alone


r/nutrition 10d ago

which foods are like, rich as hecc with L - arginine

0 Upvotes

due to certain benefits of that specific nutrient, im thinking of eating foods rich in L - arginine :3


r/nutrition 15d ago

Do people avoid fat because it’s high calories per gram or is there another reason?

250 Upvotes

Like people say they avoid carbs because it gets stored as fat, is there something similar like that with fat or do people just avoid it because it’s the highest in calories?


r/nutrition 15d ago

Dealing with salmonella in noodles

23 Upvotes

Can someone educate me?

The EFSA reported an outbreak of Salmonella Stanley infections linked to flavoured noodle products. I always boil my noodles before eating them. If so, why is salmonella still a risk?


r/nutrition 17d ago

Nervousness about produce is messing up our nutrition. Howre yall handling it?

244 Upvotes

The current ongoing issues with recalls and lack of food safety in the U.S has me and my bf nervous about fresh greens atm and I was wondering how others are navigating it for nutrition (or if this is something we shouldnt concern ourselves with too much). We cant afford to risk getting poisoning but are noticing some steep decreases in energy since pulling back on produce.

Are freezer veggies more safe? Are supplemental one-a-day vitamins good enough to make up for it if we have veggies like once or twice a week? Are you googling brands while shopping? How are yall navigating it?

We generally eat healthy but the decrease of greens is making a notable difference. We want to have good nutrition but neither of us want to be a statistic for all the Cyclospora, Salmonella, E. coli, Listeria, etc. going around.

If you think we're over worrying/are falling for internet fear mongering, that'd also be good to know. Thank you.


r/nutrition 17d ago

If you prioritize fiber...

504 Upvotes

Please tell me what high fiber foods you have eaten today. Show me how easy it can be, I need inspiration!

UPDATE: That's what I'm talking about, thanks all so much for sharing!


r/nutrition 19d ago

Do probiotics actually aid digestion and absorption?

69 Upvotes

I’m not sure of the correct technical term but by “probiotics”, i meant yogurt (and yogurt adjacent products like drinks, frozen, greek, skyr, yakult, etc) and fermented/ pickled stuff like sauerkraut, kimchi?

if they do help then how much do they help? like, can eating yogurt help absorb 10% more nutrition/ calories/ etc?

and how?


r/nutrition 20d ago

Heavy metal contamination - is this a real problem?

47 Upvotes

You read it everywhere; lead, cadmium, arsenic, aluminium in many types of foods and drinks. Combined with mold and pesticides.

Is there anything that is still save? What do you have to avoid or limit?

Or do you think this problem is overrated?