Keto has a great PR team. It promises fast weight loss, fewer cravings, and the satisfying feeling of putting butter on things without whispering,
“Is this… allowed?” But here’s the plot twist: a growing body of research suggests that some “keto-like” low-carb, high-fat eating patterns may
raise heart-risk markersand may even be linked to roughly double the risk of serious cardiovascular events.
Before anyone panic-tosses their cauliflower rice into the void, let’s slow down and do what the internet rarely does: read past the headline.
The real story is more nuanced (and more useful). It’s less “carbs are evil” vs. “fat is evil,” and more “your food choices have consequences,
and your arteries do not care about vibes.”
The headline in plain English
The phrase “keto-like” matters. Many people hear “keto” and picture a carefully planned diet with non-starchy vegetables, fish, olive oil, nuts,
and modest portions of cheese. Others hear “keto” and interpret it as a permission slip for processed meats, heavy cream, and a heroic amount of bacon.
These are not the same plan. And that differenceespecially the type of fat and overall food qualityis where heart
health tends to win or lose.
When headlines warn that “keto-like low-carb diets may double your risk,” they’re usually referring to a low-carb pattern that’s also high
in fat (often saturated fat) and frequently lower in fiber-rich foods. That combination can increase LDL (“bad”) cholesterol and related
particles that are strongly tied to atherosclerosis (plaque buildup in arteries).
What the “keto-like” study actually found
One of the most-cited “double the risk” reports came from research presented at a major cardiology meeting that analyzed participants who self-reported
eating a low-carbohydrate, high-fat patternroughly defined as getting 25% or less of daily calories from carbs and more than
45% from fat. Compared with a matched group eating a more standard pattern, the low-carb/high-fat group had higher levels of LDL cholesterol
and apolipoprotein B (apoB), and they experienced a higher rate of major cardiovascular events over follow-up.
The attention-grabbing phrase “twofold” (about double) came from the observed difference in event rates between groups. The events tracked included
outcomes like heart attacks and strokes, and also other serious problems such as angina or needing procedures like stenting.
Two key markers: LDL cholesterol and apoB
LDL cholesterol gets most of the spotlight, but apoB deserves a cameoand maybe a starring role. ApoB is a protein found on the surface
of atherogenic particles (the ones that can contribute to plaque). In simple terms: LDL cholesterol tells you how much cholesterol is being carried;
apoB hints at how many “delivery trucks” are on the road. More trucks can mean more chances for cholesterol to end up where it shouldn’tlike inside
artery walls.
Many people on very-low-carb, high-fat diets see triglycerides drop and HDL (“good”) cholesterol rise, which feels like a win. But if LDL and apoB
climb significantlyespecially into high-risk rangesthat’s not a cosmetic issue. That’s a risk signal with a long history in cardiovascular science.
What “double the risk” means (and what it doesn’t)
“Double the risk” sounds like a guaranteed disaster. It’s not. It’s a statistical association: the low-carb/high-fat group, as a whole, had a higher
rate of events than the comparison group. That does not prove the diet directly caused the events. Observational studies can be influenced by
confounding factors (exercise habits, smoking, stress, genetics, medical care, how the diet was implemented, and how accurately people reported it).
Still, observational evidence mattersespecially when it aligns with a known biological pathway (higher LDL/apoB → more plaque risk over time). In other
words: you don’t need perfect proof to take a red flag seriously.
Why some low-carb plans can backfire on the heart
A low-carb approach can be built from salmon, olive oil, walnuts, tofu, and vegetables… or from processed meats, butter, and cheese “snacks” that come
in a shiny bag. One of those patterns has decades of supportive evidence for cardiovascular health. The other has a talent for sending LDL cholesterol
into orbit.
1) Saturated fat can push LDL upward
Saturated fatscommonly found in fatty red meats, butter, full-fat dairy, and many processed foodstend to raise LDL cholesterol in many people.
Major heart-health organizations consistently recommend limiting saturated fat and emphasizing unsaturated fats (from foods like olive oil, nuts,
seeds, and fish) as part of a heart-protective pattern.
The problem isn’t “fat” in general. It’s what fat replaces, and the overall dietary pattern around it. Swapping refined carbs for
unsaturated fats and high-fiber foods can be beneficial. Swapping fiber-rich carbohydrates for lots of saturated fat and processed meats is where
things often go sideways.
2) Fiber often gets cut… and your arteries notice
Many keto-like plans dramatically reduce fruits, legumes, and whole grainsthe foods that supply soluble fiber. Soluble fiber helps reduce LDL
by binding bile acids in the gut, nudging the body to use cholesterol to make more bile. Translation: fiber is like a tiny cleanup crew that works
overtime when you feed it.
When fiber drops, people may also lose the blood-sugar stability and gut-health support that plant foods provide. Some keto followers do eat plenty
of non-starchy vegetablesexcellent. But many “grab-and-go keto” routines don’t come close.
3) “Keto snacks” can mean more salt and ultra-processed foods
Not all keto foods are ultra-processed, but the market sure is. Packaged “keto bars,” processed meats, and cheese-heavy convenience meals can drive up
sodium intake, which can raise blood pressure in salt-sensitive individuals. Blood pressure is one of the biggest modifiable risk factors for heart
disease. Your heart does not get bonus points because the label says “keto-friendly.”
4) Some people are dramatic LDL “responders”
Individuals vary widely. Some see little change in LDL; others see major increases on very-low-carb, high-fat patterns. Case reports and clinical
observations describe people whose LDL rises sharply on ketogenic diets and falls substantially when they stop or modify the diet. Genetics likely
play a role, including predispositions toward high cholesterol.
But aren’t low-carb diets sometimes helpful?
Yessometimes. Many studies show that reducing refined carbohydrates and added sugars can improve weight, triglycerides, and short-term blood sugar
control, especially for people with insulin resistance or type 2 diabetes. Some people feel fewer cravings and eat fewer calories without constantly
fighting hunger. That matters.
The key is separating carb quality from carb quantity. “Low-carb” can mean fewer sugary drinks and less white bread
(great), or it can mean fewer fiber-rich foods and more saturated fat (not great). Research increasingly suggests that “healthy low-carb” patterns
emphasizing plant foods and unsaturated fats can differ dramatically in long-term outcomes compared with “unhealthy low-carb” patterns heavy in animal
fats and processed meats.
Also important: long-term adherence is a real-world issue. A diet that works for eight weeks but collapses at month four can turn into a cycle of
regain, frustration, and “I guess I’ll eat cheese standing in front of the fridge.” Sustainable habits usually beat heroic restriction.
Who should be extra careful with keto-like low-carb diets
Low-carb approaches aren’t automatically off-limits, but certain groups should be especially cautiousor avoid keto-like extremes unless supervised
by a clinician:
- People with known heart disease (history of heart attack, stroke, stents, or significant plaque)
- Those with high LDL cholesterol or a family history suggesting inherited cholesterol disorders
- Anyone with diabetes on glucose-lowering medications (risk of hypoglycemia if carbs drop quickly)
- People with kidney disease or conditions where high protein intake may be risky
- Those with uncontrolled high blood pressure (especially if relying on salty processed foods)
- Pregnant people or those with a history of eating disorders (restrictive patterns can be destabilizing)
Even if you’re not in these categories, it’s smart to treat keto-like dieting like you’d treat a new gym routine: start thoughtfully, monitor how your
body responds, and don’t assume the loudest influencer is your cardiologist.
How to make a low-carb approach more heart-friendly
If you like the appetite control or blood-sugar steadiness of eating fewer carbs, you don’t necessarily have to abandon the idea. But you do need to
build it in a heart-aware way. Think of it as “low-ish carb, high-ish quality.”
Prioritize unsaturated fats
Aim for fats from foods like olive oil, avocado, nuts, seeds, and fatty fish. These choices are more aligned with heart-healthy dietary guidance than
basing your fat intake on butter, processed meats, and heavy cream.
Keep fiber in the plan (yes, even on low-carb)
Load up on non-starchy vegetables (leafy greens, broccoli, cauliflower, peppers, mushrooms). If your carb target allows, add small portions of berries,
beans/lentils, or minimally processed whole grains. If you’re strict keto, pay extra attention to fiber from vegetables, chia/flax, and nutsand consider
discussing it with a registered dietitian.
Choose protein like you care about your future self
Favor fish, poultry, and plant proteins more often, and limit processed meats (bacon, sausage, deli meats). Processed meats are repeatedly linked to
worse cardiovascular outcomes in broad nutrition research, and they tend to ride in on a wave of sodium and saturated fat.
Monitor your labs, not just your waistband
If you adopt a keto-like pattern, consider checking a lipid panel (and discussing apoB if available) after about 6–12 weeks. If LDL or apoB jumps,
don’t argue with the numbers. Adjust the planespecially by reducing saturated fat and increasing unsaturated fats and fiberor consider a different approach.
A quick “keto-like” red-flag checklist
- Your daily fats come mostly from butter, fatty red meat, and cheese
- Vegetables are more of a garnish than a habit
- You rely heavily on processed “keto” products
- Your LDL cholesterol or apoB rises substantially after starting
- You’re ignoring blood pressure, sleep, stress, and movement (the unglamorous heart-health MVPs)
The bottom line
The “keto-like diets may double your risk” headline isn’t a moral judgment on low-carb eating. It’s a warning that certain versionsparticularly those
high in saturated fat and low in fibermay elevate LDL/apoB and are associated with higher rates of cardiovascular events in observational research.
If you’re doing low-carb for weight or blood sugar, you can often keep the benefits while reducing the heart risks by emphasizing unsaturated fats,
fiber-rich plants, and minimally processed foodsand by monitoring cholesterol markers instead of assuming everything is fine because the scale moved.
Medical note: This article is for education, not personal medical advice. If you have cardiovascular risk factors or take medications, consult a qualified clinician before making major diet changes.
Real-World Experiences: What People Notice on “Keto-Like” Low-carb Diets
People’s experiences with keto-like low-carb diets often follow a familiar arckind of like a streaming series that starts strong, hits a weird plot
twist in episode five, and then forces you to decide whether you’re still emotionally invested.
Experience #1: “I feel amazing… and then my cholesterol ruins the party.”
A lot of people report an early “honeymoon” phase: fewer cravings, steadier energy, and fast weight loss (some of which is water weight as glycogen
stores shrink). Clothes fit better. The afternoon slump disappears. They start evangelizing to friends with the confidence of someone who has just
discovered the miraculous powers of cauliflower.
Then labs happen. LDL cholesterol is upsometimes a little, sometimes a lot. This is where people feel betrayed, because they were told that eating
fewer carbs automatically means better heart health. The reality is more conditional: if the diet is heavy on saturated fat (butter, fatty meats,
full-fat dairy) and light on fiber, the body may respond by increasing LDL and apoB. And that isn’t a theoretical concernit’s a measurable shift
tied to long-term atherosclerosis risk.
Experience #2: “I did keto… but I basically just ate ‘keto junk food.’”
The modern food environment makes it very easy to do “keto” without doing “nutrition.” People get busy, so breakfast becomes processed sausage and
cheese, lunch becomes a bun-less fast-food burger, and snacks become “keto bars” that taste like chocolate and ambition. The carb count may be low,
but sodium and saturated fat can be sky-high. Vegetables show up occasionallyusually as a decorative lettuce leaf bravely trying to escape.
Over time, some notice issues that don’t show up on the macro tracker: constipation (low fiber), rising blood pressure (sodium), fatigue (too few
micronutrient-rich foods), or workouts that feel harder (carbohydrates do have a purposeyour muscles would like a word). None of this happens to
everyone, but it’s common enough that clinicians and dietitians routinely warn people not to confuse “low carb” with “heart smart.”
Experience #3: “Keto worked… until it didn’t.”
Sustainability is the quiet factor behind most diet outcomes. Some people thrive long-term on a thoughtfully built low-carb planespecially one that
leans into unsaturated fats, seafood, nuts, seeds, and lots of vegetables. But others find strict keto socially and practically exhausting. Travel,
family dinners, and holidays turn into math problems. They white-knuckle through it for months, then rebound into “well, I’ve already blown it” eating.
A common pivot is moving from strict keto to a more flexible, heart-aware approach: moderate carbs from high-fiber sources, fewer refined carbs, and
fats coming mostly from olive oil, nuts, and fish rather than butter and processed meats. People often report they still feel stable and less hungry,
while their LDL improvesor at least stops climbing like it’s training for a mountain race.
Experience #4: “I learned my body has opinions.”
Perhaps the most valuable real-world lesson is that bodies vary. Two people can eat “the same” keto-like plan and see totally different cholesterol
responses. Some barely budge; others spike dramatically. That’s why individualized monitoring matters. A scale, a ketone meter, and a macro app can’t
tell you what your arteries are doing. A lipid panel can.
If there’s one takeaway from people’s lived experiences, it’s this: keto-like dieting isn’t automatically a heart-health villain, but it’s not
automatically a hero either. The food choices and biomarker response determine whether the story ends in “I found a
sustainable pattern” or “my cardiologist and I are now pen pals.”
