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First, apropo nothing whatsoever (except that I happened upon it in a search for [ chia ] here in the forums), I hope everyone has read MIchael's Nutrition and Supplementation for Veg(etari)ans.

 

Now, my question: I hear and read much about people getting their omega-3 needs met by flax seeds or flax seed oil, or, for some of us, fish, others, supplements, but I don't hear much about chia seeds. Is there some problem with them I haven't seen?

 

I created an Excel spreadsheet with 250 calorie amounts of nuts, a few seeds, and a few other fatty items in order to help guide my fatty food choice, and was amazed at how nutritious chia seeds are!

 

They're bland-tasting, to be sure -- is that why people don't get excited about them? Otherwise, lots of minerals, but no scary amounts of Cu or Mn (though not really low Mn), far more vitamins than most nuts or seeds, even a lot of carotenoids. Fairly low SFA, to boot. And then all that ALA.

 

Is there some hidden danger?

 

Zeta

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I will summarize my recollection of digging I did on this subject some time ago, in hopes that I am not grossly misrecalling and that an unreferenced memory may prove more useful than remaining silent for lack of documentation:
 
It is my recollection that when I looked into the question some time ago, the bioavailability of ALA from chia seemed to be quite substantially lower than that from flax — in some studies, invoving whole chia seed, extremely low. To be clear, I don't believe I found any studies directly comparing bioavailability of ALA from flaxseed vs. chia: rather, I saw studies comparing flaxseed (ground or whole) and/or oil, finding oil > ground seed > whole seed, and (separately) studies looking at whole and ground chia, finding ground > whole, such that (approximately, IIRC, assuming no major methodological confounder that made the studies not comparable) bioavailabilities were flax oil > ground flaxseed > intact flaxseed > ground chia (yes) > whole chia. The issue was hypothesized to be the high level of very viscous soluble fiber, which bound up the fatty acids in chia and prevented their absorption.
 
Additionally, Paleo diet researcher Loren Cordain endorses flaxseed but not chia seed as a source of plant omega-3, for entirely different reasons:
 

Flaxseed is an excellent source of the omega 3 fatty acid alpha linolenic acid (ALA). I can no longer recommend chia seeds for the following reasons.

 

At least on paper, it would appear that chia seeds are a nutritious food that is not only high in ALA, but also is a good source of protein, fiber, certain B vitamins, calcium, iron, manganese and zinc.  Unfortunately, ... As is the case with many other plant seeds (e.g., cereal grains, legumes) chia seeds contain numerous antinutrients which reduce their nutritional value.  [High phytate content is the only one that he explicitly lists; he also mentions the low bioactivity of plant forms of B6 -MR] ...

[The] clear mucilaginous gel that surrounds the seeds ... forms a barrier which impairs digestion, fat absorption and causes a low protein digestibility.  Based upon animal and human studies, it is likely that other antinutrients together with this gel may promote a leaky gut, chronic systemic inflammation and food allergies. Dr. Nieman and co-workers recently completed a study in humans who consumed 50 grams of chia seeds per day for 12 weeks.  At the experiment’s end both men and women experienced increases in a blood inflammatory marker called interleukin 6 (IL-6).  After 12 weeks the men’s blood levels of IL-6 increased 10.2 %, and the women’s increased 10.1%. Additionally, another inflammatory marker called monocyte chemotactic protein increased 6.9 % in the men and 6.1 % in the women.

 

In support of the notion that chia seed consumption may adversely affect the immune system and promote inflammation is a rat study showing that after only one month high chia seed diets increased blood levels of IgE by 112.8 %.  Because IgE is a marker for allergenic food proteins that are processed through the gut, chia seeds likely cause a leaky gut and food allergies.

 

I also don't care for the relatively high carb content of chia seeds, which I have to regard as largely empty, dense Calories.

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Michael,

 

Thanks for your thoughts on chia seeds. I could be wrong, but my reading of the evidence doesn't seem to come down so much in favor of flax seeds over chia seeds as you suggest, at least from an Omega-3 bioavailability perspective. I found one study [1] directly comparing flax (seed and oil form) and chia (seed and oil form) head-to-head. Unfortunately it was in chickens. Nevertheless, it found that the eggs from hens fed chia seeds or chia oil were significantly more enriched with ALA than hens fed flax seeds or flax oil (comparing whole seed with whole seed and oil with oil). This would seem to contradict your recollection / interpolation that whole flax seeds were better than ground chia seeds wrt ALA, and in fact gives the head-to-head advantage to chia over flax wrt to ALA bioavailability. But of course, that is in chickens.

 

In people (postmenopausal women to be exact), this study [2] ground chia seeds (25g/day for seven weeks) do appear to increase ALA (+138%) and EPA (+30%). But no comparison with the effects of flax seed on blood levels of omega-3s was made in this study, or any other I've found. 

 

Regarding inflammation, flax has been well documented to reduce markers of inflammation [3][4]. As for chia seeds and inflammation, I couldn't find any studies showing an increase in inflammation from chia seeds as (dubious Paleo researcher IMO) Lorain Cordain suggests. I did however find several studies by the researcher he references (Neiman) to dismiss chia, including [2] mentioned above (which found favorable results w/ chia). In the study by Neiman that seemed to most closely match Cordain's description [5], overweight men and women consumed 50g/day (whole?) chia seeds or placebo for 12 weeks. At the end, the chia eaters saw a 25% increase in blood ALA relative to controls, but no improvement in markers of inflammation or other health markers. Here is a quote from the abstract of [5]:

 

Pre-to-post measures of body composition, inflammation, oxidative stress, blood pressure, and lipoproteins did not differ between [chia seed] and [placebo] for both sexes.

 

So inflammatory markers did not get worse in chia consumers relative to controls, as Cordain says in his (apparent) description of this study. But then again, inflammation didn't get better either.

 

In another Neiman study [6], this time in runners, chia seed oil (1g/kg bodyweight) increased acute plasma ALA (+337%), but didn't not improve running performance or blunt the post-exercise spike in inflammatory markers. But again inflammation wasn't worse after chia supplementation, and no comparison was made with flax.

 

From a nutritional perspective, chia has less total fat, less ALA and less MUFA than flax per equal size portion. And it does have more carbs (+13g/100g serving) relative to flax, but half of that is in the form of extra soluble fiber. 100g of chia seeds has over twice as much calcium as flax seeds (631 vs. 255 mg) - but neither is a superstar on a per-calorie basis.

 

Overall, I think you assessment is correct - flax seeds appear to be a somewhat better CR food than chia seeds, based on the (limited) evidence I could find. But I don't think chia seeds are quite as inferior to flax as your recollection (and Lorain Cordain's misrepresentation) seem to imply.

 

--Dean

 

----------------

[1] Br Poult Sci. 2011 Dec;52(6):750-60. doi: 10.1080/00071668.2011.638621.

Omega-3 enriched egg production: the effect of α -linolenic ω -3 fatty acid
sources on laying hen performance and yolk lipid content and fatty acid
composition.

Antruejo A(1), Azcona JO, Garcia PT, Gallinger C, Rosmini M, Ayerza R, Coates W,
Perez CD.

Author information:
(1)Fac. Cs. Veterinarias-Universidad Nacional de Rosario, 2170-Casilda,
Argentina.

1. Diets high in total lipids, saturated fatty acids, trans fatty acids, and
having high ω-6:ω-3 fatty acid ratios, have been shown to be related to increased
instances of coronary heart disease, while diets high in ω-3 fatty acids have
been shown to decrease the risk. 2. Feeding ω-3 fatty acid diets to laying hens
has been shown to improve the quality of eggs produced in terms of saturation and
ω-3 content. 3. A study was undertaken to determine if the ω-3 fatty acid source,
when fed to hens, influences the amount transferred to eggs. 4. Flaxseed and
flaxseed oil, along with chia seed and chia seed oil, were the two main sources
of ω-3 fatty acid examined during the 84 d trial. 5. All α-linolenic enriched
treatments yielded significantly higher ω-3 fatty acid contents per g of yolk and
per yolk, than the non-α-linolenic enriched diets. Chia oil and chia seed yielded
54·5 and 63·5% more mg of ω-3 fatty acid per g of yolk for the 56 d test period,
and 13·4 and 66·2% more for the 84 d test period, than flaxseed oil and flaxseed,
respectively. 6. The differences in omega-3 content were significant, except for
the chia oil compared with the flax oil, at the end of the trial. 7. This trial
has shown that differences in conversion exist among ω-3 fatty acid sources, at
least when fed to hens, and indicates that chia may hold a significant potential
as a source of ω-3 fatty acid for enriching foods, thereby making these foods a
healthier choice for consumers.

PMID: 22221241

 

---------------------------

[2] Plant Foods Hum Nutr. 2012 Jun;67(2):105-10. doi: 10.1007/s11130-012-0286-0.

Supplementation of milled chia seeds increases plasma ALA and EPA in
postmenopausal women.

Jin F(1), Nieman DC, Sha W, Xie G, Qiu Y, Jia W.

Author information:
(1)Human Performance Lab, North Carolina Research Campus, Plants for Human Health
Institute, Appalachian State University, 600 Laureate Way, Kannapolis, NC 28081,
USA. Fuxia.Jin@dole.com

Ten postmenopausal women (age 55.6 ± 0.8 years, BMI 24.6 ± 1.1 kg/m²) ingested 25
g/day milled chia seed during a 7-week period, with six plasma samples collected
for measurement of α-linolenic acid (ALA), eicosapentaenoic acid (EPA),
docosapentaenoic acid (DPA), and docosahexaenoic acid (DHA). Subjects operated as
their own controls with overnight fasted blood samples taken at baseline (average
of two samples), and then after 1, 2, 3, 5, and 7 weeks supplementation. Plasma
ALA increased significantly after one week supplementation and was 138 % above
baseline levels by the end of the study (overall time effect, P < 0.001). EPA
increased 30 % above baseline (overall time effect, P = 0.019) and was correlated
across time with ALA (r = 0.84, P = 0.02). No significant change in plasma DPA
levels was measured (overall time effect, P = 0.067). Plasma DHA decreased
slightly by the end of the study (overall time effect, P = 0.030) and was not
correlated with change in ALA. In conclusion, ingestion of 25 g/day milled chia
seeds for seven weeks by postmenopausal women resulted in significant increases
in plasma ALA and EPA but not DPA and DHA.

PMID: 22538527

 

------------------

[3] Indian J Exp Biol. 2011 Dec;49(12):932-8.

Anti-inflammatory, analgesic and antipyretic activities of Linum usitatissimum L.
(flaxseed/linseed) fixed oil.

Kaithwas G(1), Mukherjee A, Chaurasia AK, Majumdar DK.

Author information:
(1)Department of Pharmaceutical Sciences, Faculty of Health & Medical Sciences,
Allahabad Agricultural Institute-Deemed University, Allahabad 211 007, India.

The fixed oil of L. usitatissimum (flaxseed/linseed) inhibited PGE2-,
leukotriene-, histamine- and bradykinin-induced inflammation. The oil also
inhibited arachidonic acid-induced inflammation, suggesting its capacity to
inhibit both cyclooxygenase and lipoxygenase pathways of arachidonate metabolism.
In tail immersion model, the oil raised the pain threshold to a lesser extent
than morphine but showed excellent peripherally acting, analgesic activity
comparable to aspirin, against acetic acid-induced writhing in mouse. In typhoid
paratyphoid A/B vaccine-induced pyrexia, the oil showed antipyretic activity
comparable to aspirin. The oil contains 57.38% alpha-linolenic acid. Dual
inhibition of arachidonic acid metabolism, antihistaminic and antibradykinin
activities of the oil could account for the biological activity and the active
principle could be alpha-linolenic acid an omega-3 (18:3, n-3) fatty acid.

PMID: 22403867

 

------------------

[4] Nutr J. 2015 Jan 10;14:5. doi: 10.1186/1475-2891-14-5.

Impact of weight loss diet associated with flaxseed on inflammatory markers in
men with cardiovascular risk factors: a clinical study.

Cassani RS, Fassini PG(1), Silvah JH, Lima CM, Marchini JS.

Author information:
(1)Department of Medicine, Division of Medical Nutrition, Ribeirão Preto Medical
School, University of São Paulo, Avenida Bandeirantes, 3900 Bairro Monte Alegre,
CEP: 14049-900, Ribeirão Preto, São Paulo, Brazil. priscilafassini@usp.br.

BACKGROUND: Flaxseed has received attention for its anti-inflammatory and
antioxidant role. The present study hypothesizes if flaxseed added to a weight
loss diet could improve the lipid and metabolic profiles and decrease risk
factors related to cardiovascular disease.
METHODS: In a prospective, single blinded 42 days protocol, subjects were
allocated into two groups with low carbohydrates intake: GriceLC (35% of
carbohydrate and 60g of raw rice powder per day) and GflaxLC (32% of carbohydrate
and 60g of flaxseed powder per day). Blood pressure, anthropometric measures and
serum levels of isoprostane, C-reactive protein, Tumor Necrosis Factor-alpha,
glucose, lipidic profile, uric acid, adiponectin, leptin and insulin were
measured at baseline and at the end of interventions. Serum and urinary
enterodiol and enterolactione were also measured.
RESULTS: A total of 27 men with cardiovascular risk factors were evaluated, with
mean age of 33 ± 10 years to GriceLC and 40 ± 9 years to GflaxLC. Both groups
experienced weight loss and systolic blood pressure reduction. A decrease in
inflammatory markers (CRP and TNF-α) was observed after flaxseed intake (mean
decrease of 25% and 46% for GflaxLC respectively). All groups also showed
improvement in levels of total cholesterol, LDL-c, uric acid and adiponectin.
Only GflaxLC group showed a decrease in triglyceride levels.
CONCLUSION: This study suggests that flaxseed added to a weight loss diet could
be an important nutritional strategy to reduce inflammation markers such as CRP
and TNF-α.
TRIAL REGISTRATION: ClinicalTrials.gov NCT02132728.

PMCID: PMC4326402
PMID: 25577201

 

-----------------

[5] Nutr Res. 2009 Jun;29(6):414-8. doi: 10.1016/j.nutres.2009.05.011.

Chia seed does not promote weight loss or alter disease risk factors in
overweight adults.

Nieman DC(1), Cayea EJ, Austin MD, Henson DA, McAnulty SR, Jin F.

Author information:
(1)Department of Health, Leisure, and Exercise Science Appalachian State
University, Boone, NC 28608, USA. niemandc@appstate.edu

The objective of this study was to assess the effectiveness of chia seed (Salvia
hispanica L) in promoting weight loss and altering disease risk factors in
overweight adults. The hypothesis was that the high dietary fiber and
alpha-linolenic (ALA) contents of chia seed would induce a small but significant
decrease in body weight and fat and improve disease risk factors. Subjects were
randomized to chia seed (CS) and placebo (P) groups, and under single-blinded
procedures, ingested 25 g CS or P supplements mixed in 0.25 L water twice daily
before the first and last meal for 12 weeks. Ninety nondiseased, overweight/obese
men and women between the ages of 20 and 70 years were recruited into the study,
with 76 subjects (n = 39 CS, n = 37 P) completing all phases of the study. Pre-
and poststudy measures included body mass and composition (dual energy x-ray
absorptiometry), inflammation markers from fasting blood samples (C-reactive
protein, interleukin 6, monocyte chemoattractant protein 1, and tumor necrosis
factor alpha), oxidative stress markers (trolox equivalent antioxidant capacity
and plasma nitrite), blood pressure, and a serum lipid profile. Plasma ALA
increased 24.4% compared to a 2.8% decrease in CS and P, respectively
(interaction effect, P = .012). No group differences were measured for changes in
plasma eicosapentaenoic acid and docosahexaenoic acid (interaction effects, P =
.420 and .980, respectively). Pre-to-post measures of body composition,
inflammation, oxidative stress, blood pressure, and lipoproteins did not differ
between CS and P for both sexes. In conclusion, ingestion of 50 g/d CS vs P for
12 weeks by overweight/obese men and women had no influence on body mass or
composition, or various disease risk factor measures.

PMID: 19628108

 

--------------------

[6] Nutrients. 2015 May 15;7(5):3666-76. doi: 10.3390/nu7053666.

No positive influence of ingesting chia seed oil on human running performance.

Nieman DC(1), Gillitt ND(2), Meaney MP(3), Dew DA(4).

Runners (n = 24) reported to the laboratory in an overnight fasted state at 8:00
am on two occasions separated by at least two weeks. After providing a blood
sample at 8:00 am, subjects ingested 0.5 liters flavored water alone or 0.5
liters water with 7 kcal kg-1 chia seed oil (random order), provided another
blood sample at 8:30 am, and then started running to exhaustion (~70% VO2max).
Additional blood samples were collected immediately post- and 1-h post-exercise.
Despite elevations in plasma alpha-linolenic acid (ALA) during the chia seed oil
(337%) versus water trial (35%) (70.8 ± 8.6, 20.3 ± 1.8 μg mL(-1), respectively,
p < 0.001), run time to exhaustion did not differ between trials (1.86 ± 0.10,
1.91 ± 0.13 h, p = 0.577, respectively). No trial differences were found for
respiratory exchange ratio (RER) (0.92 ± 0.01), oxygen consumption, ventilation,
ratings of perceived exertion (RPE), and plasma glucose and blood lactate.
Significant post-run increases were measured for total leukocyte counts, plasma
cortisol, and plasma cytokines (Interleukin-6 (IL-6), Interleukin-8 (IL-8),
Interleukin-10 (IL-10), and Tumor necrosis factors-α (TNF-α)), with no trial
differences. Chia seed oil supplementation compared to water alone in overnight
fasted runners before and during prolonged, intensive running caused an elevation
in plasma ALA, but did not enhance run time to exhaustion, alter RER, or counter
elevations in cortisol and inflammatory outcome measures.

PMCID: PMC4446772
PMID: 25988762

Edited by Dean Pomerleau

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If bioavailability of ALA from chia seeds is super-low (and 75% of the fat from them come from ALA), then isn't this an argument for consuming chia seeds from a pro-CR perspective? Since it just means one can eat more chia seeds with much smaller increases to one's calorie consumption!!

Edited by InquilineKea

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Alex,

 

Have you found evidence that the bioavailabililty of ALA from chia seeds is super-low, or are you basing that on Michael's (potentially mistaken) recollection?

 

If chia seed ALA is indeed lower in bioavailabililty than say, flax seeds, whether that makes them a more "pro-CR" food or not depends on your objective.

 

If all you are hoping to do is get eat more volume without many calories, there are a lot less expensive and effective ways to do it than (allegedly) chia seeds. Even within the nuts and seeds group, swallowing whole (unshelled) sunflower or pumpkin seeds, will do the trick as well :-). Psyllium husks are also (like chia) high in soluble fiber, and won't give you many calories.

 

But if you're buying (relatively expensive) chia seeds in hopes of absorbing their healthful nutrients (including ALA), and if the nutrients in chia seeds have been shown to have limited bioavailabililty due to their anti-nutrient content or mucilaginous coating when wet, then it sort of defeats the purpose.

 

--Dean

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Have you found evidence that the bioavailabililty of ALA from chia seeds is super-low, or are you basing that on Michael's (potentially mistaken) recollection?

 

Just basing it on Michael's recollection, which (slightly) updates me in reduced ALA bioavailability, which I may investigate a bit more when I have more free time.

 

 

 

Even within the nuts and seeds group, swallowing whole (unshelled) sunflower or pumpkin seeds, will do the trick as well :-). Psyllium husks are also (like chia) high in soluble fiber, and won't give you many calories.

 

Hm that's a good idea. I do fear that the shells could do long-term stochastic damage to my teeth/gums b/c they're often spiky. I should look into psyllium husks more.

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If all you are hoping to do is get eat more volume without many calories, there are a lot less expensive and effective ways to do it than (allegedly) chia seeds. Even within the nuts and seeds group, swallowing whole (unshelled) sunflower or pumpkin seeds, will do the trick as well :-). Psyllium husks are also (like chia) high in soluble fiber, and won't give you many calories.

 

Isn't bioavailability of ALA in whole (unground) flaxseed also rather low? http://www.ncbi.nlm.nih.gov/pubmed/18689552

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Alex,

 

Isn't bioavailability of ALA in whole (unground) flaxseed also rather low?

 

Yes - of course. Like many seeds, their tough coating makes them pass right through you undigested if you don't mechanically break them up. In the case of small seeds like flax, it is virtually impossible to break them up with your teeth, so grinding them into flax meal, or "juicing" them into flaxseed oil is the only way to effectively access their Omega-3 ALA. 

 

So don't waste your money eating whole flax seeds, unless it is for satiety purposes.

 

--Dean

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