1. What are triglycerides?

Triglycerides are the form in which dietary fat is stored in our fat tissue (adipose tissue), which is mainly found under the skin of our belly and buttocks. Scientists draw triglycerides that look like a trident or jellyfish, depending on how look at it.

When eating food with fat in it, the fat is in triglyceride form. Digestion breaks it down into individual fatty acids (and glycerol) which get absorbed through the intestine and rebuilt into triglycerides that then get packaged into their first transport vehicle called chylomicron, the largest of the apolipoprotein particles. The picture below is of a chylomicron.

1.1 Blood test – fasting serum/plasma triglycerides

Triglycerides are not only stored in fat cells and tissues, they’re also carried around the body as a passenger in these particles. This is what is measured in the the lab tests called fasting plasma triglycerides or fasting serum triglycerides: the concentration of triglycerides within apolipoprotein particles travelling through the bloodstream.

This lab test usually occurs after an overnight fast (9 – 12 hours) because if triglyceride levels are measured after a short meal instead they will be much higher, thus more so reflecting that particular meal rather than a general baseline metabolic state. Taking the test after fasting makes it easier to compare triglyceride levels of different people fairly – everyone is fasted for the test.

Interestingly, Robb Wolf speculates that extending the overnight fast to about 14 – 16 hours for people on low-carb or ketogenic diets is a simple precaution . Why? Slowly digesting a large fatty meal could still ‘drip feed’ triglycerides from the gut into blood-bound particles. The idea has a leg to stand on!

Although triglycerides are measured when fasting that doesn’t mean that they don’t somewhat reflect the quality of diet. Triglyceride levels are responsive to poor food choices (e.g. pizza) and reflect chronic metabolic ‘insults’ accruing over time that are mal-adaptive to one’s health, longevity and performance. In fact, some doctors use the fasting triglycerides blood test to double-check whether or not their patients are actually following their advice to significantly lower their total dietary carbohydrates and entirely remove the worst sources like refined starches and added sugars.

Clearly, fasting blood triglycerides have a lot to teach us about our current state of health; it is even included as 1 of the 5 criteria for Metabolic Syndrome, which is a pernicious physiological state from which many diseases like diabetes, Alzheimer’s and obesity can grow out of.

The ‘opposite’ of Metabolic Syndrome is often considered to be metabolic flexibility. At the level of the organs and bloodstream this desirable metabolic quality is the smooth cycling of triglycerides between liver and adipose tissue, both attentively ‘listening’ to all the cells ‘shouting’ their moment-to-moment and longer term energy needs.

Although triglycerides are a well understood health marker, discoveries are still being made about them – like the fact that they can reach our brains in small amounts by crossing the blood brain barrier .

1.2 What triglycerides are composed of

Back to the basic for a second before we get back to the health aspects. Triglycerides are composed of 3 fatty acids and 1 glycerol molecule. The ‘tri’ in triglyceride refers to 3 fats (or fatty acids), that may be saturated or otherwise. The ‘glyceride’ part refers to glycerol.

All triglycerides have a glycerol and 3 fatty acids but whether those fatty acids are more or less saturated varies from triglyceride to triglyceride. To some extent, the ratio of saturated to unsaturated fatty acids that triglycerides are composed of reflects dietary patterns, specifically how many carbs you eat and the kind of fats you eat as well as how much . Unfortunately, knowing what an individual’s triglycerides are composed of exactly doesn’t point to a clear treatment versus another – hopefully someday soon!

1.3 What does the triglycerides structure look like?

Glycerol is a sort of backbone to which the 3 fatty acids stick. Fun fact, if you were to taste glycerol on its own it’d be sweet! About 60% as sweet as glucose.

You can think of triglyceride structure as a versatile form to store fats, both in the de facto energy buffer (adipose tissue) and lipoprotein particles when mobilized to the bloodstream. Our adipose tissue ensures energy delivery to cells remains nice and smooth whether we’re gorging on a five course meal or running hills after 24 hours without food.

Like a cleverly built lego piece, the triglyceride structure is purpose-built to quickly respond to changing energy demands. The triglyceride structure can be quickly disassembled (e.g. for digestion) and assembled (e.g. for storage). It’s versatile.

When disassembled, the 3 ‘free’ leftover fatty acids can now can circulate in the bloodstream (not within lipoproteins) or find themselves in cells being shuttled straight into the ‘‘engines’ (mitochondria), like wood in a stove. The glycerol ‘backbone’ is also left over from this disassembly and is free to go where needed, whether that’s to make new glucose, amino acids, fat or keep the TCA cycle going. The TCA cycles stands for the tricarboxylic cycle, the final common pathway where all fuels (fats, protein and carbohydrates) get used up via oxidation inside the little cellular engines called mitochondria.

So clearly we need triglycerides to stay alive. But too much of a good thing can be bad sometimes.

2. What are symptoms of high triglycerides?

When triglyceride levels starting creeping up to 500 mg/dL (5.6 mmol/L) pancreatitis can occur, an inflammation of the pancreas. It’s often accompanied by pain, vomiting, nausea, a loss of appetite and fever. In this instance very high triglycerides are having obvious acute negative effects, but what about longer term effects or less acute symptoms of high triglycerides?

According to Metabolic Syndrome criteria, having triglycerides ≥ 150 mg/dL (1.7 mmol/L) is considered ‘high’. Although at this level pain or obvious symptoms don’t manifest. What they represent is the tip of the proverbial disease iceberg; they are a strong risk marker for serious diseases like cardiovascular disease and diabetes.



For cardiovascular disease, men with the highest triglycerides in a group with high triglycerides (capped at 300 mg/dL or 3.4 mmol/L) were found to have a 823% increased (relative) risk of coronary heart disease when followed for 5.5 years !

For type 2 diabetes, absolute risk increases from 2.3% to 9.2% in men with triglycerides under and over 124 mg/dL (1.4 mmol/L), respectively. . These figures come from men with BMIs under 25 with normal fasting blood glucose levels under 100 mg/dL (5.5 mmol/L).

3. How to lower high triglycerides

Interestingly, average triglyceride levels in US adults dropped from 126 to 97 mg/dL (1.4 to 1.1 mmol/L) during the 14 years from 1999/2000 to 2013/2014 . It’s unclear if this decrease is good or bad, if it is even meaningful in the clinical sense and if they are, what factors are responsible.

Maybe low-calorie and low-fat recommendations from national dietary guidelines could have contributed, for better or for worse. Or the ongoing use of statins and other medications that may lower triglycerides could have contributed. Whatever the case, it’s far from clear.

Medications are usually a doctor’s first attempt to lower triglycerides but this intervention is typically underwhelming to say the least. Another way to lower triglycerides involves following this heuristic (a simple yet imperfect rule):

manipulate lifestyle factors such as diet, exercise and sleep that are capable of affecting your energy status and hormonal profile

You have to get these 2 aspects of your biology right in order for your fat cells (adipocytes) to properly manage the entry and exit of fuels, like triglycerides, from the bloodstream.

This is because the most direct, meaning proximate reason for high triglycerides building up in the blood is fat tissue’s inability or unwillingness to keep on expanding and multiplying in order to keep on storing more and more incoming triglycerides

Fasting, whether done intermittently for 12 – 16 hours or in a prolonged manner for more than 24 hours, can lower triglycerides safely . Maybe this happens because you end up eating less overall (quantity) or because you’re eating less often (frequency).

After all, multiple small meals throughout the diet tends to raise triglycerides and is a recent dietary pattern for humans from an evolutionary point of view. Reverting to a less frequent eating pattern of 2-3 meals a day with the rare snack may be a smarter default pattern to roughly aim for.

Walking for 30 minutes or for even just a few minutes multiple times within 2 hours of a meal can substantially lower the level of triglycerides following that meal . Exercise, specifically medium-intensity training or high-intensity training can lower fasting triglycerides by 15.3 mg/dL (0.17 mmol/L) and 15.7 mg/dL (0.18 mmol/L), respectively . Resistance training over 16 weeks, even in 25 otherwise sedentary male smokers, can lower fasting triglycerides 18.4% from 1.2±0.5 to 0.8±0.06 mmol/L (106.3 to 70.9 mg/dL) .

A lowER-carb diet with 168.5g/day of carbs, so not a ‘real’ low-carb diet, reduced fasting triglycerides by 31.1±36 mg/dL (0.35 mmol/L) after 6 months in breast cancer survivors . Women with hypertriglyceridemia who dropped the carbs in their diet from 50% to 35% of calories – also not a truly low-carb diet – saw a small 10 mg/dL fall in their fasting triglycerides from 126±36 to 116±57 mg/dL (1.4 to 1.3 mmol/L) . After a year, diabetic men and women on a ketogenic diet lowered their fasting triglycerides by 48±16 mg/dL (0.54 mmol/L) on average .

Calorie restriction (…when eating a crappy diets) can also lower fasting triglyceride values. This is seen repeatedly with primate studies .

It’s also seen in human intervention studies using various diets . It should be emphasized that chronic calorie restriction is not a sustainable, and thus clever long-term way to lower triglycerides. Calorie restriction is best achieved when achieved intermittently and somewhat spontaneously as a result of a normalized appetite, possibly thanks to an improved metabolism and better hormonal profile.

Circadian entrainment: think of it as the computer integrating information from your liver clock, your adipose clock, your muscle clock and so on so that your cells run smoothly throughout the day and night. It is the proper syncing of your biological clocks with environmental cues, especially the light and dark cues.

Skipping straight to the punch line of what this implies…indoor lighting at night might not be a harmless modern luxury but a significant factor interfering with basic metabolic and endocrine (hormonal) activity in the long-term . Triglyceride levels and other measures of metabolism can reflect circadian disruptions .

This is why medical studies are starting to take very seriously things like shift work and night eating with regards to metabolic dysfunction. One study says:

“Put simply, due to circadian regulation of metabolism, eating a Big Mac at night is not the same as eating a Big Mac during the daytime”

Don’t eat Big Macs, but if you do eat them during the day. Anecdotally, a significant obstacle to this is late-night drinking and its impairing effect on decision making

3.1 What foods cause high triglycerides?

Vegans and carnivores probably both agree that one good answer to the question What foods cause high triglycerides? is something like “Big Macs!”. They’ll disagree as to why, but eating Big Macs practically guarantees your triglycerides will either creep up or shoot up over the long-term for 2 reasons:

One reason is because the burger has added sugars and a bun made of flour, both of which cause the hypersecretion of the hormone insulin . This locks more fat into fat cells, until they no longer can or ‘want’ to, and so start ‘leaking’ triglycerides into the bloodstream which then accumulate over time.

Secondly, seed oils like sunflower, canola and soybean oil are in most condiments and are commonly used to cook fast food. When consumed in the amounts the average person does, they are highly inflammatory, act as mitochondrial disruptors and are metabolized to toxic compounds such as acrolein, a known toxin, which is also present in cigarette smoke .

So, What foods cause high triglycerides? Junk food or even home-cooking using flour, added sugars and seed oils. Meals with a lot of these ingredients tend to be conspicuously low in levels of quality animal protein, potentially further exacerbating the rise in triglycerides.

Such low quality food ingredients more than just raise triglycerides; it enables Metabolic Syndrome itself to develop – some hypothesize due to excessive ‘oxidative stress’ . In simpler terms, oxidative stress is analogous to the sparks, rattles and bangs coming from the engine of a tired old car being driven with the wrong fuel.

3.2 The foods to avoid with high triglycerides

You should be thinking of the foods to avoid foods if you have high triglycerides reaching or surpassing 100 mg/dL (1.1 mmol/L).

For the most part, the foods that shot your triglycerides up in the first place are the ones you must certainly avoid. More likely than not, that is a mix of things like pizza, cakes, bread, biscuits, pasta, sugary sauces, sodas, fruit juices, sandwiches, sports gels, sugary sports drinks etc..

You get the idea, avoid stuff made from flour and cooked or containing (high omega-6) seed oils. The only unfortunate add-on to this is that once triglycerides are already high, you are less likely to be able to handle sources of carbohydrate that may otherwise be fine for you, like potatoes, beans or fruit.

3.3 The importance of triglycerides synthesized in the liver

Having ‘low’ fasting triglycerides below 100 mg/dL (1.1 mmol/L) is important, but so is having the right amount of newly created triglycerides within your liver. Unfortunately you can’t measure this as of yet because the test isn’t available to the public. However, understanding why this measure important is particularly useful for people with excessive liver fat, the disease NASH (non-alcoholic fatty liver disease) or another such problem.

De novo lipogenesis (DNL) means ‘the creation of new lipids’ and triglycerides can be made in the liver through DNL. Triglycerides synthesized in adipocytes affect how many of them end up in the bloodstream and in the liver. 25% of triglycerides synthesized in the liver come from DNL in someone with NASH, another 60% comes from leaky fat cells and 15% comes directly from the fat in the diet.

What this means is that your metabolic health is strongly tied to the health of your fat cells.To keep your fat cells functioning correctly it’s advisable to follow the simple heuristic of keep your insulin needs low. This can help make choices clearer when it comes to dietary, sleep and exercise habits.

Only seen in alcoholics a few decades ago, it’s amazing that alcoholic liver disease is now common to non-alcoholics eating lots of sugar and flour products. This is why the disease is now called NASH). Triglycerides synthesized in the liver on such low quality diets accumulate at such speed that saturated (palmitic) fat increases in the blood (within VLDL particles specifically). Although this is associated with bad health outcomes it’s important to know that the amount of saturated fat in the diet itself isn’t associated with this negative change.

3.4 Are low triglycerides always good?

That depends on your cut-off for ‘low’. In general low triglycerides are a good thing because more than a rapidly growing third of Americans are diagnosed with Metabolic Syndrome, a diagnosis which can include high triglycerides ≥ 150 mg/dL (1.7 mmol/L). So what was high a generation ago is now getting closer and closer to being ‘average’ and thus, sadly, normal.

However, low triglycerides can be too low. Or at least they can be below that which is considered optimal whilst being associated with ill health. This is quite uncommon but has been associated with autoimmune conditions like Sjögren’s syndrome and rheumatoid arthritis . Dr.Tommy Wood relates his clinical experience where he’s seen low triglycerides (below 50 mg/dL or 0.6 mmol/L) in individuals chronically over-exercising and/or under-eating .

All that being said, low triglycerides as a general health worry should not be in the minds of the the vast majority of people. The opposite is a much better concern to check out with a cheap blood draw.

4. What about medication for high triglycerides?

Going down the path of medication for high triglycerides is a losing battle. In essence, niacin and fibrates are the main options as well as statins to a much smaller degree.

In two large clinical trials, no benefit from niacin therapy was found for reducing heart disease events, and this despite the fact that the drugs lowered triglyceride levels and raised the level of “heart-healthy” cholesterol . Clearly, how one lowers fasting blood triglycerides matters more than simply lowering them by hook or by crook.

Even metformin, a rather well-regarded drug for people with Metabolic Syndrome with few side effects, doesn’t lower triglycerides any more than a placebo does when given on top of a ‘lifestyle intervention’ .

It seems lifestyle interventions geared towards lowering your overall need for insulin is a good default approach rather than diving head first into medication for high triglycerides.