The triglyceride bands (fasting)
| Triglycerides, mg/dL (mmol/L) | Band | Where the line comes from |
|---|---|---|
| Under 90 (under 1.0), no lower limit | Optimal | Phoenix choice. Inside the American Heart Association's "optimal" fasting level of under 100 mg/dL. |
| 90 to under 150 (1.0 to under 1.7) | Monitor | Phoenix band. Worth working on. |
| 150 or higher (1.7 or higher) | Talk to your doctor | Guideline line. The top of the healthy range; 150 to 199 is "borderline high". Bring it to your next appointment. It is not an emergency. |
The line rule. "Under 90" excludes 90, and "150 or higher" includes 150. So 90 is Monitor and 150 is Talk to your doctor.
No lower limit. A low triglyceride result is never marked as a problem.
Confidence in the optimal line: moderate for the heart. There is no brain reason to push triglycerides lower.
Why is there no lower limit?
Because the brain data point the other way. In older adults, higher triglycerides went with less dementia, not more.
- In 18,294 adults aged 65 or older without dementia (the ASPREE trial), whose median triglycerides were 106 mg/dL, each doubling of triglycerides went with an 18% lower dementia rate (hazard ratio 0.82). The result held in the 13,976 people with APOE data and in the UK Biobank (hazard ratio 0.83), and higher triglycerides also went with slower memory decline (Zhou, 2023).
- In the UK Biobank, the direction flipped with age: higher triglycerides went with more dementia in people under 60, and less dementia from 60 on (Gong, 2022).
- In a 20-year Chicago cohort, higher triglycerides went with slower cognitive decline in ε4 carriers only (Ng, 2025).
The ASPREE authors think high-normal triglycerides may mark better overall health. Either way, nothing supports pushing them very low, so Phoenix sets no floor. If you are under 60, keep them in range: that is the age group where high triglycerides went with more dementia.
What does APOE4 change about triglycerides?
Almost nothing. Across 82 studies of 86,067 healthy people, the APOE genotypes moved LDL cholesterol in a straight line, but the link with triglycerides was largely confined to people with ε2/ε2 (Bennet, 2007). A carrier's triglyceride target is the same as anyone else's.
Why do triglycerides matter for the heart?
Because triglyceride-rich particles carry ApoB, and ApoB is what your arteries feel. In a 2019 study of 63 cohorts, gene variants that lower triglycerides cut coronary heart disease by exactly as much as their drop in ApoB, the same as gene variants that lower LDL-C: 23% lower odds per 10 mg/dL less ApoB. Once ApoB was counted, triglycerides added nothing (Ference, 2019).
Trials show the same thing. Pemafibrate cut triglycerides by 26%, but ApoB rose 4.8% and heart events did not fall (hazard ratio 1.03) (Das Pradhan, 2022). So when your triglycerides come down, check that your ApoB comes down with them.
What do the guidelines say?
- American Heart Association (2011): a fasting triglyceride level under 100 mg/dL is "optimal" (Miller, 2011).
- US National Library of Medicine: healthy under 150 mg/dL, borderline high 150 to 199, high 200 to 499, very high 500 or higher (MedlinePlus, 2024).
- ACC/AHA (2018): triglycerides that stay at 175 mg/dL or higher are a risk-enhancing factor (Grundy, 2018).
- American Heart Association (2019): 200 to 499 mg/dL is hypertriglyceridemia, and 500 or higher is very high (Skulas-Ray, 2019).
These lines were written for heart risk. None was built from carrier data.
Why did Phoenix choose under 90?
I chose under 90 because it sits inside the American Heart Association's "optimal" range with a margin, and it is the line Phoenix's app has always used. Under 100 would match the guideline exactly; the 10-point difference was not worth two sets of numbers.
I also removed the old 40 mg/dL floor that Phoenix's Blood Work Blueprint used to print. Nothing supported it, and the brain data above point the other way.
How do you get triglycerides tested?
Triglycerides come on every standard lipid panel. For this band, use a fasting result: the National Library of Medicine says you may need to fast for 9 to 12 hours (MedlinePlus, 2024). After normal meals, triglycerides rose by up to 0.3 mmol/L (about 27 mg/dL) and stayed up for as long as 6 hours (Langsted, 2008). A non-fasting result can land you a band too high.
High triglycerides also distort a calculated LDL-C. When triglycerides were 200 to 399 mg/dL and the old formula said LDL-C was under 70, the measured value was really under 70 only 40% of the time (Martin, 2013). If yours are high, add an ApoB test.
Units: divide mg/dL by 88.6 to get mmol/L. 90 mg/dL is 1.0 mmol/L and 150 mg/dL is 1.7 mmol/L.
What moves triglycerides?
Triglycerides respond to what you eat and drink faster than almost any other marker. Ranked by size of effect:
- Prescription omega-3, 4 g a day: 30% or more lower. In people with very high triglycerides, 4 g a day of EPA plus DHA lowered them by 30% or more. EPA alone at 4 g a day cut major heart events by 25% in high-risk patients on a statin (Skulas-Ray, 2019). These are prescription doses, well above a typical fish-oil capsule.
- Fibrates: about 26% lower. Pemafibrate lowered triglycerides by 26.2%, but ApoB rose and heart events did not fall (Das Pradhan, 2022).
- Weight loss: about 4 mg/dL per kg. With diet and exercise, each kilogram lost lowered triglycerides by 4.0 mg/dL at 12 months (Hasan, 2020). Losing 10 kg is worth about 40 mg/dL.
- Fewer carbohydrates: about 23 mg/dL lower. Low-carbohydrate diets lowered triglycerides by 0.26 mmol/L more than low-fat diets, while LDL-C rose about 6 mg/dL (Mansoor, 2016).
- Less sugar: about 10 mg/dL. Higher sugar intakes raised triglycerides by 0.11 mmol/L in randomized trials (Te Morenga, 2014).
- Less alcohol: about 6 mg/dL per two drinks a day. 30 g of alcohol a day raised triglycerides by 5.7 mg/dL (Rimm, 1999).
- Aerobic exercise. On its own, it lowered triglycerides in trials, even without a diet change (Kelley, 2012).
Statins lower triglycerides as well, and the response does not differ by APOE genotype (Zintzaras, 2009).
Omega-3 is the most logged supplement among Phoenix members (184 members, as of 2 October 2026), and in Release 001 omega-3 was a repeated pattern across triglycerides, hs-CRP, vitamin D or HDL in eight members.
How often should you retest?
Retest 4 to 12 weeks after a change, then every 3 to 12 months. That is the ACC/AHA schedule for lipid tests after starting or adjusting a lipid medicine or a lifestyle change (Grundy, 2018). Triglycerides move fast, so 4 weeks is often enough to see a diet change.
Confirm a high result before you act on it. The 2018 guideline counts triglycerides as a risk factor when they stay high, so repeat a high reading with a fasting test.
What Phoenix members actually do: for triglycerides, the median span between a member's first and latest test is 308 days, about ten months.
My numbers
I carry APOE4/4. My triglycerides have never been the problem:
| Date | Triglycerides | Band |
|---|---|---|
| 13 December 2024 | 35 mg/dL (0.4 mmol/L) | Optimal |
| 7 August 2025 | 56 mg/dL | Optimal |
On that same December panel, my LDL-C was 139 mg/dL. Low triglycerides did not mean my lipids were fine, which is why I test ApoB every time. This is one carrier's result.
What Phoenix members' results show
Triglycerides are where most Phoenix members already do well. Of 203 Phoenix members who uploaded a triglyceride result (as of 2 October 2026), 158 (78%) have a latest value under 90, 40 (20%) sit between 90 and under 150, and fewer than 10 are at 150 or higher. The median is 67 mg/dL. Members with two copies of APOE4 look the same (121 members, 78% under 90).
They are also the easiest lipid to fix. Of 38 members who started above 90 and tested again, 21 (55%) got under 90, a far better rate than for LDL-C, where 17% of members who started above the optimal line got under it. Of 81 who started under 90, 74 (91%) stayed there. In the 476-member Phoenix Research Release 001, 56 of 100 repeat testers lowered their triglycerides.
One member shows how fast it can go. An APOE4/4 man in his 50s, on an omega-3 stack, went from 154 to 61 mg/dL (60% lower) in 102 days. He also started a statin near his follow-up test; the report notes it began too late to explain a change already under way.
Most member results do not record whether the person fasted, so read these as the lab reported them.
When should you talk to your doctor?
Talk to your doctor if your fasting triglycerides are 150 mg/dL (1.7 mmol/L) or higher. Bring the result with your ApoB and LDL-C, and ask whether to repeat it fasting.
At 500 mg/dL or higher, triglycerides are in the "very high" category (MedlinePlus, 2024; Skulas-Ray, 2019). Bring that result to your doctor promptly rather than at a routine visit.
Between 90 and under 150, the result is worth working on, and the food and drink levers above are where most people start. If you take a medicine for your lipids, keep it exactly as prescribed and bring any change to your doctor.