Question 1

Is there a scientific study that I can read that will back up these claims?

Accepted Answer

Absolutely, there are studies!  There are enough that I need to ask you to be more precise in what you want to know.  Which ingredient are you interested in, for what population, and concerning what symptoms?  Your local library may be able to help you access research databases that will allow you to search to your heart's content.  State libraries may be used by any taxpayer, and some medical schools will allow community members a day pass.  Here is a little taste, notice how long this research has been going on: 1) Weisberg, I., Tran, P., Christensen, B., Sibani, S., & Rozen, R. (1998). A second genetic polymorphism in methylenetetrahydrofolate reductase (MTHFR) associated with decreased enzyme activity. Molecular genetics and metabolism, 64(3), 169-172.2) Grandone, E., Margaglione, M., Colaizzo, D., Cappucci, G., Paladini, D., Martinelli, P., ... & Di Minno, G. (1997). Factor V Leiden, C> T MTHFR polymorphism and genetic susceptibility to preeclampsia. Thrombosis and haemostasis, 77(6), 1052-1054.3) (The title for this one is unfortunate, it is a randomized, controlled clinical study which is the gold standard, and it found the reduced B vitamins to work to alleviate symptoms of major depression as well as homocystine levels. 4) Sontag, J.-M., Wasek, B., Taleski, G., Smith, J., Arning, E., Sontag, E., & Bottiglieri, T. (2014). Altered protein phosphatase 2A methylation and Tau phosphorylation in the young and aged brain of methylenetetrahydrofolate reductase (MTHFR) deficient mice. Frontiers in Aging Neuroscience, 6, 214. http://doi.org/10.3389/fnagi.2014.00214There is your taste!  There is also research showing lack of/poor sperm count in males with homozygous A1298C variant of MTHFR, higher risks of pre-eclampsia in pregnant women, etc., etc.,  At this point, I'm surprised that routine screening has not yet become a standard of care.  I hope that the variation of research articles here has helped you to understand why a more precise question is needed for a direct answer.  No single study will do it (and never does).  How about 2 decades of research?  :)

Question 2

Ingredients?

Accepted Answer

There seems to be some confusion about the difference between Methyl-Guard and Methyl-Guard PLUS, which costs twice as much as the regular Methyl-Guard listed on this page.Jana B.'s answers above seem to list the ingredients of the plus version, although the amounts appear to match that of the regular version. (?)This version does NOT have Riboflavin (B2) (Riboflavin 5'-Phosphate Sodium). In addition to B2, the plus version also claims to have more of all of the ingredients listed below.I have never purchased MG-Plus but I have a bottle of the regular Methyl-Guard in front of me.Here are the ingredients as listed:3 capsules contain:Vitamin B6 (as Pyridoxal 5'-Phosphate)   20.4 mg   1,020% DVFolate (as L-5 Methyltetrahydrofolate from L-5 Methyltetrahydrofolic Acid, Glucosamine Salt)   1.2 mg   300% DVVitamin B12 (as Methylcobalamin)   1.2 mg   20,000% DVBetaine Anhydrous (Trimethylglycine)   1.8 g   *DV not establishedOther Ingredients:Hypromellose (derived from cellulose) capsuleCalciumCitrateLaurate  (sic)Silicon DioxideSuggested Use: Take 3 capsules two times daily or as recommended by your health-care practitioner. (Personally, I only take 3 a day, not 6)

Question 3

This states 180 capsules???

Accepted Answer

Thorne Research - Methyl-Guard comes in a 180 capsule sized bottle.

Question 4

What is the difference between the old label and the new label?

Accepted Answer

Also some of the amounts are different. 
Old methyl guard:
Three Capsules Contain:
Vitamin B6 (as Pyridoxal 5'-Phosphate) 20.4 mg.
Folate (1.2 mg as L-5-Methyltetrahydrofolate† from L-5-Methyltetrahydrofolic Acid, Glucosamine Salt) 2 mg DFE
Vitamin B12 (as Methylcobalamin) 1.2 mg.
Betaine Anhydrous (Trimethylglycine) 1.8 g.

New Methyl guard Plus:
Three Capsules Contain:
Riboflavin (as Riboflavin 5'-Phosphate Sodium) 90 mg
Vitamin B6 (as Pyridoxal 5'-Phosphate) 45 mg
Folate (3 mg as L-5-Methyltetrahydrofolate† from L-5-Methyltetrahydrofolic Acid, Glucosamine Salt) 5 mg DFE
Vitamin B12 (as Methylcobalamin) 3 mg
Betaine Anhydrous (Trimethylglycine) 1.8 g

This is from the thorne research website.
I love the old one (helps with depression) but the plus gives me a migraine.

ASIN	B0012FJVA2
Age Range Description	Adult
Allergen Information	Shellfish Free
Best Sellers Rank	#641 in Health ( See Top 100 in Health ) #43 in Multiple Vitamin-Mineral Combination Supplements
Brand	THORNE
Brand Name	THORNE
Color	red
Container Type	Bottle
Country of Publication	USA
Customer Reviews	4.7 out of 5 stars 1,056 Reviews
Diet Type	Gluten Free
Diet type	Gluten Free
Dosage Form	Capsule
Flavor	Unflavored
Flavour	Unflavored
Global Trade Identification Number	00693749787037
Item Dimensions	7.3 x 7.3 x 13.3 centimeters
Item Form	Capsule
Item Weight	180 Milligrams
Item form	Capsule
Manufacturer	Thorne Research
Manufacturer Part Number	SF787-R
Material Type Free	en_AE
Model Name	Methyl-Guard
Number of Items	1
Primary Supplement Type	Vitamin B and Folate
Primary supplement type	Vitamin B and Folate
Product Benefits	Bone Health Support
Product benefits	Bone Health Support
Specific Uses For Product	Heart
UPC	693749787037 885335121343 884733360033 885100656025 881619227596
Unit Count	180.0 Count

THORNE Methyl-Guard - Supports Methylation for Healthy Heart, Blood Vessels, Brain & Bones* - Vitamins B6 & B12, Folate (5-MTHF) & Betaine - Gluten, Dairy & Soy-Free - 180 Capsules

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