Celery Juice: Scam or superfood?
Whoever thought the juicing trend, would be short lived, was wrong. That was me, I was wrong. As we have found with many “super foods” there is a whole lot of hype before we actually hear the science behind the trend (?). So what about celery juice?
Quite often people do not realise that by smashing one cup of veggie juice each day they are unlikely to get enough of whatever active ingredient is in the aforementioned vegetable, fruit or magical unicorn dust to see an effect. However there will be enough sugar to negatively effect insulin sensitivity.
Another important consideration: If you could get enough for an effect, would it be safe? Studies are often done using highly concentrated extracts, usually in animal experiments (modals), because they don’t know if this highly concentrated extract is safe.
Is celery juice effective, and is it even safe?
What are the claims?
Let’s get down to understanding what some people are claiming around celery juice.
- Fat loss
- Fertility improvements
- Reduces inflammation
Ok, now let’s look at these claims in more detail. To do so let’s look at celery in more detail.
Celery is a vegetable that has firmly staked its place as part of a delicious Bloody Mary, and a variety of dishes. Part of the Apiaceae family, the long stalk, and leaves are all edible. When raw, celery is crunchy and not particularly strong in flavour (unless you hate that flavour). When cooked in casseroles/stews, it breaks apart easily adding healthful fibre to these dishes.
What is celery made up of?
According to Food Standards Australia New Zealand, (FSANZ), Celery is as follows.
|Dietary fibre||1.4 g|
|Retinol equivalents||10 mg|
|Beta carotene||58 mg|
According to FSANZ, juicing only really removes the fibre, so celery juice provides a very similar nutrient profile. As it has such a high water content, you are unlikely to have a super concentrated juice, so you will have to drink a lot of it. Some websites are recommending up to a pint.
Losing fibre to juicing is always a shame. Fibre is a great part of all veggies, providing important benefits to our bowel health as well as gut bacteria. People in general do not eat enough fibre (or vegetables, or fruit!!). If this sounds like you, try and eat your food before juicing it.
As you can tell and probably taste, there isn’t much to celery, it’s mostly water. However there are some phytonutrients present. Phytonutrients are chemicals found in plant-based food that can have anti-oxidant properties.
We already know that vegetables are a good source of antioxidants, so why do we need to juice them or get more? The answer is we don’t. Eating a variety of vegetables and fruit each day, reaching your 5 and 2 should be enough to maintain a healthy body.
Why do researchers use concentrated amounts?
There can be confusion as to why the science community try to isolate them and use higher amounts. Reasons the science community uses concentrated extracts:
- Curiosity, to observe cause and effect, science only use the active ingredient
- To detect negative effects, safety and toxicity.
- A cure for cancer and other chronic diseases and social diseases such as obesity.
These are valid reasons for research, however it doesn’t mean the average person needs these phytochemicals in higher isolated amounts. Research results get picked up by the media, and the food then becomes a “super food”, even though all veggies are super, great for you, and a whole lot cheaper in whole food form.
What phytonutrients in celery have caught the attention of the science community?
|Luteolin, one of the most scrutinised.|
Kaempferol Quercetin also found in green tea, apples and berries.
Apigenin, the most abundant flavonoid in celery.
|Caffeic acid, also found in coffee.|
P-coumouric acid the most abundant phenolic acid in celery
What does the research actually say?
There is currently no research on celery juice, but there are journal articles on celery leaf extract and the phytonutrients found in celery. To further complicate matters, the research is mainly in animals, which we cannot easily generalize to people. As such we do our best to conjecture what this research means for humans. As always the focus is on how safe are these products for you, as well as how effective.
It would appear that celery leaf extract can stimulate the production of thyroid stimulating hormone (TSH). TSH is a hormone produced by the pituitary gland, found just under the brain. The role of TSH is to stimulate the thyroid into making two hormones, T4 and T3.
About 75% of the hormone produced at one time by the thyroid is T4 and the remaining 25% is T3. T4 can also be turned into T3. These two hormones (T4 & T3) increase the metabolism of every tissue in the body. As such, anything that stimulates the production of TSH, will increase metabolism, however this can be detrimental if used in high concentrations or for a prolonged time period.
There have been two recent documented cases of celery leaf extract inducing hyperthyroidism. In a 2016 case study a man in his forties induced hyperthyroidism using 4 grams of dried celery leaves per day. Once he was treated and stopped taking the supplement his thyroid went back to normal function after two months.
A separate 2019 case study involves a 36-year old woman, taking 8 grams of celery extract daily. Hyperthyroidism induced by celery leaf extract was concluded, once Graves disease and thyrotoxicosis were ruled out. The 36-year old patient had abnormal T4 and TSH levels, and presented to hospital with blurred vision, nausea, and palpitations. Needless to say, supplementation of celery extract was immediately stopped.
Can celery extract/juice be safely used for weight loss?
So far there are no human trials in celery extracts for weight loss. There are animal modals using luteolin, the most recent looking at luteolin supplementation in mice. There was no difference found in body fat between the mice who received the supplement, and the ones who did not.
This study did find that the mice, which were obese and insulin resistant, did show improvements in insulin resistance and lowered expression of inflammatory markers. Whether this effect could be carried through into humans is unknown.
If wanting to use celery juice for weight loss, caution would best be observed. It is also good to point out that juice is inherently high in sugars and eating your vegetables with the beneficial fibre is more likely to result in long term healthy weight loss than lots of juice.
The phytonutrient of interest in fertility is luteolin. A 2014 study suggested that celery leaf extract could increase sperm count in rats, however their results are poorly reported and contradictory at times. Their images provided in the paper (mag 100x) also do not match the magnification that they state proves their theory (mag 300x). The article itself came under criticism from others in the scientific community for inaccuracies.
A more recent article looking at a different plant but the same phytonutrient profile found in celery (luteolin, quercetin, caffeic acid and ferulic acid). The 2019 paper found male rats receiving a very high dose had reduced sperm counts. Men who consume high amounts of celery extract or consistent amounts should be wary of its effect on fertility.
A 2017 systematic review, suggested celery extract could be protective for men’s sperm, but in high doses, or constant use could be damaging to sperm production. All of which sounds too vague to be used in doses above what you could eat.
These same phytonutrients which are found in celery, in concentrated extracts could also impact levels of thyroid stimulating hormone (TSH) and T4. The female rats from the 2019 study certainly had elevated levels of TSH, and pups from these female rats were abnormally overweight. This suggests over consumption could lead to hyperthyroidism and altered birth weight.
In summary, there are concerns over celery extract and hyperthyroidism, as mentioned in the two previous case studies in the fat loss section. Hyperthyroidism is contraindicative for improved fertility.
Considering the results, it would be best to keep celery consumption for men and women to the normal vegetable variety. Should you be concerned about eating celery when trying for children? No, as it is unlikely you could eat enough celery to impact your fertility.
As usual in Nutrition, it shows you can have too much of a good thing. Moderation is key, and it is why we recommend eating foods over smashing food products and supplements.
Does celery reduce inflammation? Some animal modals using celery extract have shown reduced inflammation markers. Human trials have not been done, considering how new the interest in celery and phytonutrients is. The safety of performing trials on humans is questionable. However, it is safe to say that eating a diet high in a variety of vegetables does reduce inflammation.
Considering this, it is unlikely a person would need to add lots of celery juice to their diet, at a premium cost, when they could buy vegetables and fruit for a better price and likely a more enjoyable experience. It is also not guaranteed that the antioxidants will have:
- survived the juicing process
- have been stored properly
- not been exposed to UV light or heat that would destroy the beneficial nutrients
On top of you missing out on some of the other benefits of vegetables, like fibre. Drinking more than one cup (250 mL) of fruit and/or vegetable juice a day falls into your discretionary foods.
What is a discretionary food? It is food that is usually high in sugar/fat/salt that is low in nutritional value. The Australian guidelines recommend limiting these foods. Juice is put in this category as it is often quite high in easily absorbed sugars. Juice consumed in higher quantities can play havoc with our blood glucose levels and insulin levels.
Another potential issue to consider is the dampening effects antioxidant supplementation may have on our normal oxidative stress reactions during endurance exercise. There is evidence that supplementation (high intakes of concentrated forms of phytonutrients/antioxidants) that are anti-inflammatory could reduce our own ability to react to oxidative stress caused by exercise, resulting in poor adaptations. Translated into layman’s terms this means you may not get the best muscle growth and increased insulin sensitivity from endurance training if supplementing with anti-oxidants.
Historically high supplementation of some vitamins, such as beta-carotene, vitamin A and vitamin E have been shown to increase cancer in some populations (smokers). Overall this points to just eating a variety of healthy foods over smashing supplements or juices, because we don’t know what high amounts of these antioxidants can do in certain populations. Evidence shows that they can in fact cause oxidative stress if over consumed.
Avoiding 99% if not 100% of the juicing market will make you physically and financially better off. Juice can be part of a healthy eating routine, if we see it for what it is – whole foods “not so great” mate. Just eat your veggies and fruit please.
If you want to learn more about other supplements check out our article on whether you need protein shakes.
Baek, Y. et al. (2019, Jun 20). Luteolin reduces adipose tissue macrophage inflammation and insulin resistance in post menopausal obese mice. The Journal of Nutritional Biochemistry, 71: 72-81
Bjelakovic, G. et al. (2012, Mar 14). Antioxidant supplements for prevention of mortality in healthy participants and patients with various diseases. Cochrane Database of Systematic Reviews 2012, 3.
Kooti, W. et al. (2014, Nov). The effects of hydroalcoholic extract of Apium graveolens leaf on the number of sexual cells and testicular structure in rat. Jundishapur Journal of Natural Pharmaceutical Products, 9(4), 17532
Kooti, W. et al. (2017, Oct 6). The effect of celery on fertility: A systematic review. Journal of Complementary and Integrative Medicine, 15(2).
Maciel, M. D. et al. (2019, May 6). Effects of exposure to ethanolic extract from achyrocline satureioides (Lam.) D.C. flowers on reproductive and developmental parameters in wistar rats. Journal of Toxicology and Environmental Health. Part A, 82(5): 321-330. DOI: 10.1080/15287394.2019.1593904
Maljaei, M. B. et al. (2019, May 6). Effect of celery extract on thyroid function; Is herbal therapy safe in obesity. International Journal of Preventative Medicine, 10(55).
Merry, T. L. & Ristow, M. (2015, Dec 7). Do antioxidant supplements interfere with skeletal muscle adaptation to exercise training? The Journal of Physiology, 594(18): 5135-5147.
Rouhi-Boroujeni, H. et al. (2016, Spet). Is herbal therapy safe in obesity? A case of Apium graveolens (celery) induced hyperthyroidism. ARYA Atherosclerosis, 12(5): 248-249.