I recently came across a video of Robert F. Kennedy Jr. describing a diagnosis from his doctor.

He had a full-body MRI and was told his organs were “covered in visceral fat.” The warning: he was on a fast track to atrial fibrillation. The prescription? A carnivore diet.

Thirty days later, he says he had lost 40% of that visceral fat. At his most recent scan, he claims he’s now in the 1st percentile. He also mentioned that “about half the cabinet” is following suit.

It reads a bit like a before-and-after infomercial. And like most infomercials, it raises more questions than it answers.

Because in the span of a few minutes, we jumped from a complex clinical concept (visceral fat), to advanced imaging (MRI), to an extreme dietary intervention (the carnivore diet), all wrapped into a neat cause-and-effect story.

The problem is, the body doesn’t work that cleanly. So before we start clearing out our refrigerators and stocking them with ribeyes, it’s worth slowing down and asking a few basic questions:

• Is all body fat the same?

• Does it matter where fat is stored?

• How do you lose the kind of fat that drives disease?

• And what, if anything, does a carnivore diet have to do with this?

Because when you unpack those answers, the story starts to look a lot less like a miracle.

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Isn’t fat all just… fat?

Not exactly.

We tend to talk about body fat like it’s one uniform thing. Something you either have too much of or don’t. But biologically, fat is more like real estate. Location matters. And some neighborhoods are a lot more problematic than others.

At a high level, there are three main types of body fat:

• Subcutaneous fat (under the skin)

• Visceral fat (around organs)

• Ectopic fat (inside places it doesn’t belong)

They may all store energy, but that’s where the similarity ends.

This is the fat you can pinch and likely annoys you. It sits just beneath the skin and makes up about 80% of total body fat.

It often gets lumped into the “bad” category, but it’s doing something important: acting as a safe storage system for excess calories.

Think of it like a well-organized storage unit. When excess calories come in, subcutaneous fat safely stores them away, keeping them from spilling into places they shouldn’t be.

You may not like the way it makes you look, but when it functions well, it helps you out by:

• Expanding its tissues to store energy efficiently

• Maintaining insulin sensitivity

• Preventing fat from accumulating inside your organs

In fact, lower body subcutaneous fat is associated with better metabolic health, not worse.

Visceral fat sits deep in the abdominal cavity, wrapped around organs like the liver and pancreas. Unlike subcutaneous fat, it’s metabolically active and inflammatory, which means it can:

• Releases pro-inflammatory signals

• Interferes with insulin signaling

• Drives changes in cholesterol and blood pressure

And here’s the kicker: Two people can have the same BMI but 2–3x differences in visceral fat and very different health outcomes.

Higher visceral fat is strongly linked to:

• Type 2 diabetes

• Cardiovascular disease

• Hypertension

• Increased mortality

This is the fat that shifts the conversation from cosmetic to clinical.

Ectopic fat is what happens when the system gets overwhelmed.

When subcutaneous fat can’t expand or function properly, excess fat has to go somewhere, and it starts depositing in organs not designed to store it.

That includes:

• Liver (fatty liver disease)

• Muscle (insulin resistance)

• Heart (cardiac fat deposits)

• Pancreas, kidneys, and more

Your muscles basically become a well-marbled steak. This is less about “how much fat you have” and more about where it ends up. Ectopic fat interferes directly with organ function. At this point, it’s no longer just storage; it’s dysfunction.

Yikes! So you can be within a normal weight range and have more fat than someone who is overweight?

Yep. Here’s a way to think about it…

Your body has a “safe storage unit” for subcutaneous fat (the stuff under your skin). As long as that unit has room, things stay relatively organized. But everyone’s storage capacity is different.

Some people have a small storage unit. Once it fills up, even if they don’t look overweight, fat starts getting stored in less appropriate places:

• Around organs (visceral fat)

• Inside organs like the liver and heart (ectopic fat)

That’s when problems start. It also explains why someone with a higher BMI can still have healthy biomarkers.

This is what’s called the “personal fat threshold.” You don’t need to be visibly overweight to cross it; you just need to exceed your body’s ability to store fat safely.

And in some cases, fat doesn’t even wait for overflow. Genetics and metabolic factors can send fat straight to those high-risk locations, even in people who appear lean.

So yes, someone can be “thin” by BMI standards but carry more metabolically harmful fat than someone in a larger body.

How do you accumulate these different types of fat?

There’s a typical hierarchy.

1. Subcutaneous fat fills first

2. If subcutaneous fat can’t expand, fat starts shifting inward → visceral fat increases

3. Continued overflow leads to ectopic fat

Beyond excess calories, factors like genetics, sex (men tend to accumulate more visceral fat), and age shape this.

How can I find out how much fat I have and where it is being stored?

There’s a spectrum, from quick, at-home estimates to highly precise (and less practical) imaging.

Start simple:

Waist circumference + waist-to-height ratio
These are your best low-effort signals. They don’t separate fat types, but they give a strong read on whether fat is accumulating centrally, where risk tends to climb.

How to Measure (Note: Use a flexible tape measure.)

• For waist-to-hip ratio, measure your waist at its most narrow and your hips at their widest point, and divide waist by hip

  • ≥0.90 for men and ≥0.85 for women indicates more abdominal fat and higher risk.

• For waist-to-height ratio, divide waist by your height. Aim to keep your waist less than half your height.

Basic labs: triglycerides
Pair an elevated waist with elevated triglycerides, and you’re likely looking at higher visceral fat. It’s a simple but surprisingly powerful combo.

Body composition tools (BIA, DXA)
Think of these as a step up. They estimate total and regional fat, giving you a better sense of distribution—though still not perfectly precise.

• BIA (bioelectrical impedance analysis) powers most “smart” scales. It uses a low-level electrical current to estimate fat, muscle, and water. It’s useful for tracking trends, but easily influenced by hydration and can’t tell you where fat is stored.

• DXA (dual-energy X-ray absorptiometry), best known for bone density scans, offers a more detailed breakdown of fat and muscle across the body. It’s more accurate than BIA and gives a better estimate of fat distribution, but still doesn’t directly measure fat depots or capture ectopic fat.

Then there’s the “if you really want to know” but expensive category:

MRI and CT scans
These can directly measure visceral and ectopic fat and are considered the most accurate, but they’re expensive and not routinely used unless there’s a clinical reason.

Ok, the BIG QUESTION: How do you get rid of the fat?

The answer is a bit anticlimactic: diet and exercise. But here’s the part most people miss: your body doesn’t lose all fat equally. Visceral fat (the kind around your organs) is more metabolically active, so it tends to come off faster. Think of it like clearing your kitchen counter versus organizing your garage; the visible clutter goes first once you start paying attention. Regular exercise (around 150 minutes a week) can reduce visceral fat even without major weight loss, and a modest ~5% drop in body weight can lead to a much bigger reduction in that deeper, riskier fat. Your health often improves before the scale gives you much credit.

Diet works the same way. When you lose weight, you lose fat from everywhere, but visceral fat tends to shrink first. Whether it’s Mediterranean-style, lower-carb, or just eating more intentionally, the mechanism is the same. Combine diet and exercise, and you get the best outcome: less fat where it causes problems.

Not all fat is the same.

Where it’s stored matters more than how much you have. Subcutaneous fat acts like a storage unit. Visceral and ectopic fat are where things start to break down, driving inflammation, insulin resistance, and long-term disease risk.

And while the solution isn’t flashy, it’s consistent: improve diet quality, move more, and create a sustainable energy balance. When you do that, your body preferentially reduces the fat that’s doing the most harm, even if the scale doesn’t move dramatically at first.

As for the carnivore diet?

It can lead to short-term fat loss, including visceral fat, but not because there’s anything special about it. It works by simplifying the diet so aggressively that people tend to eat less and cut out ultra-processed foods.

That same restriction is the problem. It eliminates fiber, plant diversity, and micronutrients that support heart and metabolic health, while relying heavily on foods linked to increased long-term risk.

So it works by solving one problem while creating another.

If the goal is to reduce visceral fat and protect your health, the better strategy is to build a sustainable diet that helps you lose fat without stripping away the parts that keep you healthy.

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Soy came up in class the other day.

It wasn’t planned. It wasn’t part of the lecture. It was just one of those moments where a student asked a simple question and suddenly the room split in half.

Is soy healthy?
Should we be avoiding it?
But isn’t tofu good for us and the planet?
What about breast cancer?
Doesn’t soy help with menopause symptoms?
Is this why men get “man boobs”?

I felt like I was at a tennis match.

What struck me wasn’t the questions themselves; it was how polar opposite the stances were. Soy was either positioned as a superfood or something to avoid at all costs.

So instead of picking a side, I’m going to take a look at the evidence and see what it says about soy: its benefits, its risks, and where the concerns come from.

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Soy confuses me. If it’s so good for you, why is it so controversial?

Soy sits at the intersection of three things that tend to get people worked up: hormones, cancer, and the environment. It’s not quite sex, politics, and religion, but it has the same effect on a room.

Much of the concern traces back to early research, particularly mice studies, where high doses of soy were linked to increased tumor growth. That finding stuck.

But here’s the issue:

• Mice process soy compounds differently from humans

• The doses used were far beyond what anyone would realistically eat

Meanwhile, human studies have largely shown something very different: soy foods are either neutral or protective.

Part of soy’s reputation also comes down to geography. In many Asian populations, where soy is consumed regularly in traditional forms across the lifespan, we consistently see better cardiometabolic and cancer outcomes.

In the U.S., soy tends to show up more as an ingredient than a food (think soy protein isolate or soy protein concentrate). Same source, very different context, varying effects on health.

What’s the component in soy that’s driving all of this confusion and controversy?

Soy’s entire reputation hinges on one group of compounds: isoflavones.

Isoflavones are phytoestrogens. As the name implies, they are estrogen-like compounds found in plants. But similar doesn’t mean it’s the same.

Phytoestrogens behave similarly to human estrogen, but their effects are much weaker, roughly 1/100th to 1/1000th the strength.

A note on how estrogen works in the body

Estrogen works primarily by binding to specific receptors that act as switches to turn genes on or off, controlling your development, reproduction, and many other body functions.

So…soy contains compounds that act like estrogen. I’m starting to understand the concern. Maybe I should lay off…

You don’t need to.

That’s where the nuance comes in. Think of estrogen receptors like seats at a dinner table. Human estrogen is the guest who loves to run the conversation. Phytoestrogens are able to take a seat too, but they’re more low-key, and if they are able to grab a seat, they may be able to keep that louder guest from taking over the table.

A better way to think about phytoestrogens is not as estrogen impostors, but as regulators. They are more like moderators at the table than main speakers. They adjust the tone of the conversation depending on who else is in the room.

Let’s go back to that dinner party. Imagine there are a limited number of seats. When there’s not much human estrogen around (like during menopause), phytoestrogens can step in and keep the conversation going quietly, but effectively. When estrogen is already abundant, they can take up a seat if they find one.

They don’t flood the system. They shape it.

And for the question that always comes up…

No, soy doesn’t feminize men, nor is it responsible for “man boobs”.

That narrative is built on a few extreme case reports and a lot of internet chatter. When you look at the broader body of evidence, normal soy intake, about 1–2 servings a day (roughly 25–50 mg of isoflavones), has no meaningful effect on testosterone, estrogen, or breast tissue in men.

The rare cases that do get cited? They involve very high intakes, think 3–4 quarts of soy milk a day, delivering 300+ mg of isoflavones. That’s not a dietary pattern, it’s an outlier. And importantly, those effects reversed once intake returned to normal.

Ok, so maybe soy isn’t something to fear. But is it really worth seeking out?

Once you move past the hormone panic, soy stops looking controversial and starts looking useful.

Nutritionally, here’s what it brings to the table:

• High-quality protein
  One of the few plant proteins that competes with animal protein. It’s a complete protein, which means it contains all essential amino acids and is well-absorbed.

• A healthy fat profile
  Contains no saturated fat. And when it replaces red or processed meat, that swap alone moves the needle.

• Fiber!
  A significant amount of fiber, making it a great way of reaching your fiber goal.

And the health benefits? They hold up:

• Cardiovascular health
  Soy protein can modestly lower LDL and triglycerides (~6–10%). Not dramatic, but meaningful, especially as part of a pattern (think Portfolio Diet, which I wrote about last week). The benefits likely come from the whole package: fats, fiber, micronutrients, not just isoflavones.

• Longevity & disease risk
  Higher soy intake is associated with lower all-cause mortality, along with reductions in cardiovascular and cancer-related deaths.

• Metabolic health
  Higher intake is linked to lower body weight and better metabolic markers, particularly in women.

• Bone + menopause support
  Isoflavones show modest benefits for bone density and can help take the edge off menopausal symptoms like hot flashes.

Great. But what does that actually look like in a day-to-day diet?

Like most things in nutrition, soy doesn’t work in isolation; it works as part of a dietary pattern.

Most of the benefits seen in research show up with about 1–2 servings of soy per day, which translates to roughly 25–50 mg of isoflavones.

In practice, that might look like:

• Soy milk in your coffee or cereal (about 1 cup)

• Edamame as a snack—fresh or dry roasted (about ½ cup)

• Tofu or tempeh worked into a stir-fry or grain bowl

• Miso added to soups, dressings, or marinades

  

Not a soy-heavy diet. Just a regular one, with soy as part of the rotation.

And one practical note: soy is a major allergen, so it’s clearly labeled and should be avoided by those with allergies.

Soy isn’t something to fear, and yet, it’s not a dietary must-have either.

The concerns around hormones and cancer don’t hold up when you look at the full body of evidence. In typical amounts, soy doesn’t disrupt hormones, doesn’t feminize men, and may even offer protective effects, particularly when consumed regularly over time.

What matters more is how it shows up in your diet.

When soy is eaten in its more traditional forms - tofu, tempeh, edamame, soy milk, miso - it’s a nutrient-dense food that delivers high-quality protein, fiber, and beneficial plant compounds. And like most things in nutrition, its impact is modest on its own, but meaningful as part of a broader and consistent pattern.

You don’t need to overhaul your diet. Just make room for it.

It doesn’t need a spotlight. It just needs a seat at the table.

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