How to Gain Weight on Carnivore Diets

September 6, 2025

Beginner Carnivore

by Nutrition with Judy

Most people experience significant weight loss when starting a carnivore diet. Many see their weight drop pretty quickly. And for many, that is the goal. But what if you’re on the other end of the spectrum, wanting to gain weight, build muscle, and support strength, all while staying committed to this all-animal, ultra-low-carb way of eating?

The carnivore diet isn’t just a weight-loss protocol. When approached strategically, it can be a framework for healthy weight gain, particularly in the form of lean muscle.

The key is understanding how your body builds mass, how to fuel that process with nutrient-dense animal foods, and how to adjust your eating habits to match your body’s demands. If you’ve struggled with under-eating, poor appetite, or simply haven’t seen the gains you’re aiming for, this is for you.

We’ll break down how to gain weight on a carnivore diet: from understanding how your body puts on mass, choosing the most nourishing animal-based foods, and building meals that support long-term muscle growth.

What Is the Carnivore Diet?

The carnivore diet is an animal-based way of eating. It is a zero-carb diet that removes most if not all plant foods including plant products. The carnivore diet is classified as a keto diet, only more stringent.

To be more specific, a carnivore diet consists of animal and animal products. There are different variations of the carnivore diet:

Beef-Only Carnivore Diet

This is the most restrictive but simplest among all the different types of carnivore diets. It only consists of unprocessed beef, salt, and water as your beverage. This is most commonly used as a starting diet in elimination protocol. The rationale behind this is that most people can tolerate beef. In fact, beef is ideal for those with sensitivities, autoimmune conditions, and chronic health conditions.

The beef-only diet is usually a short-term protocol. But it is also recommended for long-term healing. Over time, some foods can be introduced one at a time.

The Lion Diet

The lion diet is the second most restrictive diet in the carnivore diet variations, the difference only being the meat source. In a lion diet, other ruminant animals are considered apart from beef, plus salt and water. Ruminant animals are herbivores that have a four-chambered stomach. These are meats from cows, bison, elk, deer, lamb, goats, moose, sheep, camel, and giraffes.

The lion diet is another ideal elimination diet that is efficient in healing, symptom remission, gut and nerve healing, and suspected food sensitivities.

Nose-to-Tail Carnivore Diet

The nose-to-tail carnivore diet is also called the ancestral diet or ancestral carnivore diet. Its name gives it away—it’s a diet that includes everything from the nose of the animal to its tail. It mirrors the way our ancestors ate, in which muscle meat, organs, and bones (in our time for bone broth) were consumed.

This diet can also include fish heads and roe (eggs), raw milk, kefir, honey, and maple syrup. However, we do not recommend eating liver and kidneys daily or even weekly because they can cause vitamin A toxicity. If you really want to enjoy organ meats, we recommend eating them occasionally, in proportion to the whole animal.

Zero-Carb Carnivore Diet

The zero-carb diet is less restrictive than the previous ones because it includes anything from the animal kingdom in addition to ruminant meat. So this includes organ meats (again we don’t recommend liver and kidneys) eggs, dairy, and shellfish. That said, it makes it almost zero-carb because these foods have very small amounts of carbohydrates, but small enough that they won’t have any considerable effects.

Tea, coffee, and low-carb spices are also allowed but it all depends on your tolerance, mold sensitivities, and preferences.

Meat Only Carnivore Diet

Like the zero-carb diet, this one includes a rainbow of meats with the exclusion of organ meats. Also excluded are dairy, eggs, fish roe, honey, maple syrup, coffee, tea, and spices. True to its name, the meat-only carnivore diet includes meat.

Carnivore Keto Diet

Also called keto carnivore or ketovore, the carnivore keto diet is where the zero-carb carnivore diet and the keto diet meet. It includes what is allowed in the zero-carb diet plus fats from plants like olive oil, avocado oil, and coconut oil, sugar alternatives like monk fruit and stevia, and low-carb seasonings that have low toxicity.

While sugar-free alternatives are allowed, those with sensitivities to it or who have autoimmune conditions should be cautious because they aren’t really that well-tolerated.

Carnivore-ish Keto Diet

The carnivore-ish keto is a more flexible version of the carnivore keto diet. It’s still heavily centered on animal-based foods but allows a bit of wiggle room for plant sources that have little to no carbs like avocados and spinach. It also allows unsweetened milk and flour from nuts like almonds for beverages and baking goods.

This version offers the most variety while keeping carbs extremely low. It can work really well for people who are metabolically healthy and don’t have a lot of issues with plant anti-nutrients like oxalates or lectins.

Animal-Based Diet

This version of the carnivore diet expands to include organs, raw dairy, fruit, and honey. Fructose from fruits and honey makes this variation not keto or Carnivore. The idea is to avoid medium to high-toxicity plants.

From what we’ve seen in practice, this approach tends to work best for people who are already metabolically healthy like elite athletes or highly active individuals with stable blood sugar and good overall resilience. People who have metabolic conditions, want to lose weight, and have sugar addictions do not tolerate it well.

What Are the Benefits of the Carnivore Diet?

The carnivore diet is celebrated for its considerable health benefits including positive effects on inflammatory conditions. Research and clinical practice indicate that Carnivore can provide comprehensive symptom management for various chronic conditions along with root-cause healing for certain conditions.

The carnivore diet offers numerous benefits including improved mental clarity, better digestion, healthier skin, as well as optimized muscle and bone health to name a few. This is according to the Current Developments in Nutrition study which surveyed 2,029 people implementing the carnivore diet and self-reporting better health.

You can learn more about the key benefits of Carnivore here.

Who Should Try the Carnivore Diet?

The carnivore diet can benefit people of all ages and walks of life. It’s often recognized for helping those with chronic health conditions find relief but many healthy people choose this way of eating to fine-tune their wellness, improve energy, and simply feel their best.

When it comes to kids, though, there’s some nuance worth considering. We don’t typically recommend a strict Carnivore approach for healthy children unless they’re dealing with specific chronic conditions.

That said, a meat-forward diet that includes high-quality animal protein and healthy fats can absolutely support a child’s growth and development. But we also believe it’s important to leave room for whole-food carbs, especially for social connection, inclusion, and helping kids build a healthy relationship with food.

It’s less about rigid rules and more about teaching them how to prioritize nutrient-dense choices while still enjoying balance.

You might consider trying it if you struggle with major gut imbalances like IBS and IBD, have ongoing food sensitivities or intolerances, already follow a keto or paleo diet but want a stricter reset, are an athlete or bodybuilder curious about low or zero-carb strategies, or just want to optimize your health.

Can You Gain Weight on Carnivore Diets?

Absolutely. Though it requires intentional planning. Most people lose weight at the start of the carnivore diet, and that’s usually because they’re eating fewer calories overall, feeling fuller from all the protein and fat, and cutting out processed addictive foods. They can also achieve weight loss through ketosis and because Carnivore addresses metabolic dysfunction.

Gaining weight on a carnivore diet is absolutely doable. You just need a smart strategy.

Since this way of eating is built around fat and protein, it naturally supports weight gain when done right. By focusing on rich, fatty cuts of meat and animal foods that are rich in protein, you can easily increase your calories and start putting on a healthy weight.

To build body mass, you will need:

A consistent calorie surplus (having more calories than what the body uses daily)
A lot of protein to support muscle growth
Enough fat to fuel recovery and hormones

The same study by the Current Developments in Nutrition outlines the effectiveness of the carnivore diet in the 100 participants who are underweight and have been doing the diet for at least six months.

The study shows that 52% of them reported resolved cases, while 28% had improved cases of underweight.

Short-Term vs. Long-Term Weight Gain Considerations With Keto Diets

When it comes to metabolism, the carnivore diet works because it also drastically cuts out carbs. Without carbs, your body will go into ketosis, which is a state where it burns fat instead of glucose for fuel. This switch can impact your weight in different ways, depending on how long you stick with the diet.

In the short term, about the first three months, many people experience fast weight loss. But this early drop isn’t just about burning fat.

When you cut carbs, your body uses up glycogen, the stored form of carb, which holds onto a lot of water. As those glycogen stores deplete, the water gets released, leading to noticeable weight loss.

However, it is also important to note that there are some people who start gaining weight right away in the short-term. This could be from a variety of reasons, especially as the body is healing so macros and other refinement should be addressed later on. Working with a knowledgeable Carnivore practitioner can help troubleshoot any undesirable weight gain or weight loss.

At the same time, being in ketosis helps regulate your blood sugar and insulin levels, which can naturally reduce your appetite. As a result, many people end up eating less without trying, which leads to more fat loss.

This phase is also when people often notice less bloating, reduced joint inflammation, and improved mental clarity—things that contribute to feeling lighter, even if the scale doesn’t show it.

In the long term (beyond three months), your body becomes better at using fat for fuel, a process known as fat-adaptation. As this happens, hunger cues will start to even out. For some, their appetite can increase, especially if they’re active or focusing on strength training. This is when gaining muscle mass, becomes easier and more predictable, as long as you’re in a calorie surplus.

By this stage, the focus turns away from initial fat loss and adaptation. You can modify your diet to match your specific goals: rebuilding lost weight, building muscle, or maintaining strength.

While the first phase of the carnivore diet or keto diet often leads to weight loss, once you’re fully adapted, you’ll have more control over your energy balance. This is when gaining healthy weight, particularly lean muscle mass, becomes not only possible but sustainable too.

Tips for Gaining Healthy Weight on Carnivore

If you want to gain weight while following the Carnivore lifestyle, here are the most effective strategies:

Assessing Macros and Prioritizing Fat

Fat is a champion when it comes to gaining weight on a carnivore diet. Unlike high-carb bulking diets, Carnivore relies on fat for energy, not glucose.

Aim for:

70–80% of calories from fat
20–30% from protein

Tracking apps like Cronometer can help estimate macros, even with simple meat-based meals.

Fat-rich Carnivore Staples:

• Ribeye steak
• Pork belly
• Ground beef (70/30)
• Lamb shoulder
• Beef tallow, suet, and marrow

Don’t Sacrifice Protein Requirements

Fat gives you the fuel, but it’s protein that does the building. If you’re trying to gain weight, especially lean muscle, you need to hit your protein goals consistently. Carnivore makes this pretty straightforward.

Most animal proteins are complete, meaning they contain all the essential amino acids your body needs to repair and grow. Leucine, in particular, plays a big role in triggering muscle growth, especially when combined with resistance training.

To grow muscles, aim for around 0.8 to 1 gram of protein per pound of your goal weight. So if you’re aiming for 145 lbs, you’ll want to hit somewhere between 115 to 145 grams of protein per day.

High-quality protein sources:

Beef, lamb, venison
Eggs (6–7g protein per egg)
Fatty fish (sardines, mackerel, salmon)

Including Calorie-Dense Animal Fats

Animal fats are rich in calories (9 kcal per gram), so you can increase your calorie intake without eating large portions. Cuts like ribeye, lamb shoulder, pork belly, and added fats like tallow, suet, or marrow are great options to help you get more energy in without the extra volume. Butter is also a good and healthy option to pack on the calories.

Ideas:

Top steaks with bone marrow or butter
Add tallow into ground meat or scrambled eggs
Mix suet into burger patties
Eat fatty cuts like lamb ribs or brisket

Sample fat boosts:

1 tbsp beef tallow = 115 kcal
1 oz bone marrow = ~120 kcal
1 egg yolk = 55 kcal

Increasing Meal Frequency and Portions

If your appetite tends to disappear or you feel full quickly, try eating smaller meals more frequently throughout the day. Instead of the typical two or three meals, think four to five modest meals, or three plus a couple of snacks. This way, you can build your calorie intake without feeling like you’re constantly overeating.

That said, give your body some time to digest before bed. Ideally, wrap up your last meal a couple of hours before sleep for better digestion and recovery.

Also, portion size matters. Even small increases like 10 to 20% more per meal can help you gradually move toward your weight goals. And don’t feel pressured to make big changes overnight. Start slow: add an extra bite or two, a spoonful of tallow here or there, and let your body ease into it.

Examples:

Add a mini meal mid-morning or mid-afternoon
Increase portion sizes by 10–20% gradually

Carnivore-friendly snacks can also help bridge the calorie gap between meals. Here are some good options:

Pork rinds with butter
Hard-boiled eggs with suet
Sardines with ghee

The Impact of Exercise for Weight Gain Goals

If you’re trying to put on healthy weight, especially lean muscle, food alone isn’t going to cut it. Yes, you need to eat in a surplus, but what you do with those extra calories matters just as much. If you’re not lifting or moving your body with intention, most of that surplus is more likely to turn into fat—not strength.

Strength training can increase muscle mass. If you want your body to build functional muscle and not just store calories, you’ve got to give it a reason to. That’s why we always recommend pairing carnivore eating with a well-structured workout routine.

Start with the basics. Focus on compound lifts—the kind of movements that hit multiple muscle groups at once. Squats, deadlifts, overhead presses, bench presses, and rows. These help trigger important hormones like testosterone and growth hormone, which support muscle growth.

The key is progressive overload. This means slowly increasing the challenge: add a bit more weight, squeeze out an extra rep, or train with more intention each week. And don’t forget recovery. Your muscles grow when you rest, not while you’re working out. So get enough sleep and fuel your body with nutrient-dense meals.

Incorporate:

3–5 strength training sessions per week
Compound movements (deadlifts, squats, presses)
Progressive overload and recovery

Timing your food around your workouts can make a big difference too. After a strength session, your muscles are primed to absorb nutrients. This is your window. Get in a hearty, protein and fat-rich meal. Fasted workouts can be counterproductive to weight gain goals so eating beforehand can help too.

Post-workout meals matter. Replenish with meals like:

Ground beef with egg yolks
Lamb chops with marrow
Grilled steak with butter

Also, just to clear up a common myth: no, you don’t need to slam a sugary carb shake after lifting. If you’re already fat-adapted, your body knows how to use fat and protein to fuel recovery. In fact, many Carnivore athletes find they get stronger and recover faster without bringing carbs back into the mix at all.

While carbs can help replenish glycogen stores, a study shows that a combination of protein and fat is all you really need to kickstart muscle protein synthesis (the process that builds muscle). This is especially true if you’re already fat-adapted.

If muscle gain is your goal, you’ve got to move your body. Pair consistent strength training with calorie-dense, animal-based meals, and you’ll be on your way to steady, sustainable gains.

Addressing Stress Management

Chronic stress increases cortisol levels, which can mess with digestion and worsen gut issues. It also affects your appetite and sleep quality. Research on mice shows that long-term stress actually shrank their muscles.

High cortisol in the body can throw a wrench into everything from digestion to hormone balance. It can mess with your appetite, make sleep harder, and even shrink your muscle mass over time (we’ve seen it in research and anecdotal reports). Stress affects the hormones that help you build and maintain muscle: testosterone, insulin, thyroid hormones. When those get disrupted, your metabolism, recovery, and ability to gain healthy weight all take a hit.

It’s important to also focus on recovery and keeping your stress levels in check. Start by making sleep a priority—aim for 7 to 9 hours each night. Sleep is when your body does its best work behind the scenes: repairing tissues, producing growth hormones, and resetting your nervous system.

If you’re constantly skimping on rest, it’s going to be an uphill climb, no matter how much steak you’re eating. Without enough rest, building muscle becomes much harder, no matter how great your diet is.

Daily stress relief is non-negotiable. Whether that’s 5 minutes of deep breathing, a walk in the sun, journaling before bed, or just putting your phone away in the evening—pick something that helps your body shift out of the constant “go” mode and into rest and repair mode. That’s where the real growth happens.

It’s also important to avoid extremes. Overtraining or under-eating because you’re afraid of gaining fat? That’s a fast track to burnout. Your body needs fuel, recovery, and a nervous system that feels safe in order to thrive.

Don’t underestimate the power of sunshine and simple movement either. Getting daily sun exposure helps regulate your circadian rhythm and vitamin D levels, while walking promotes digestion, lymph flow, and mood.

In the end, a balanced, healthy nervous system is the foundation of a healthy metabolism. Stress is real, but it’s something we can learn to cope with in healthy ways. Your body wants to heal and grow but it needs you to create the space for that to happen.

Pro-Tip: If you’re looking for holistic tools for addressing stress levels, improving sleep, and community support during your weight gain journey, check out our exclusive Mind Body Program.

Closing Thoughts on Weight Gain and Carnivore Diets

Gaining weight on carnivore diets is doable and effective. Maybe you’re recovering from illness. Maybe you’re underweight from years of under-eating. Or maybe you’re simply trying to build strength and feel more grounded in your body. No matter your starting point, carnivore gives you a powerful foundation.

Remember:

Fat fuels your calorie surplus
Protein builds and preserves lean mass
Training signals muscle growth
Stress management enhances recovery and appetite

Stay consistent. Be patient with your progress. And most importantly, listen to your body. When you nourish it deeply, move it with purpose, and allow it to rest, it knows exactly what to do.

Work With Our Trusted Carnivore Diet Functional Medicine Practitioners

Our Empower Functional Health practice is honored to be trusted carnivore diet functional medicine practitioners, supporting patients and clients from around the globe. We’re passionate about helping individuals achieve root-cause healing in order to live the life they are meant to, nearly symptom-free. We provide nutritional thought leadership and evidence-based insights, paired with clinical pearls, to help you achieve your wellness goals. We welcome you to explore our free resources, and if you find that self-troubleshooting falls short, we’re here to guide you with personalized support and protocols. Our Personalized Health Plan (PHP) is the ideal starting point for uncovering your root causes. You can learn more about this powerful, proprietary tool in-depth here.

DISCLAIMER: This content is for educational purposes only. While we are board-certified in holistic nutrition and are functional practitioners, we are not providing medical advice. Whenever you start a new diet or protocol, always consult with your trusted practitioner first.