Cold all the time! Any ideas?

You put ur question under Dementia so I will assume your wife is suffering from it. This could be her problem, the Dementia. Those suffering from it tend to make more out of something than there is. Like a child.

I would have her Thyroid checked. It regulates our body temperature. If she has not had labs done in a while, I would have them done to see if it could be something else.

It's not uncommon that as we age we get cold natured, and having Alzheimer's/dementia certainly doesn't help with that either.
When my husband was still alive he too was very cold natured,(and we live in NC) and wore either sweat pants or flannel pj pants along with a hoodie sweatshirt everyday, all year round, and kept the hood up tight around his head. Either that or he wore a winter cap on his head. He also kept covered up in 2 blankets.
It sounds like you're doing what you can, but since we lose heat from our head, it may not be a bad idea to also put a hoodie or winter cap on her head as well.
Best wishes.

People lose a LOT of heat through the head. (about 7 to 10%)
Get her a cap or hat to wear. that should help a bit.
I dressed my Husband in a lot of the Polar Fleece type material. The pants were great all elastic waist so easy to pull on and off. They wash and dry very quickly.
And they are warm.
Hands and Feet loose a lot of heat as well.
Nice socks, if you check "outdoors stores" they have socks for outdoor sports that are battery operated and will stay warm. Same for mittens. If she will not wear mittens a good old fashioned Hand Muff might work.

Be very careful with the heating pads. Most now shut off after a while but heating pads can lead to burns.
If at home in a controlled area a small space heater might work as well. make sure it is in a safe area and out of her reach.

Some medications also make a person feel colder. My sister is on a Blood Pressure med and she is always cold. A friend is on a blood thinner and she also is constantly feeling cold.

Calories=heat. If she's not eating much, that can easily contribute to feeling cold. Long underwear worn underneath her clothing also helps a lot with staying warm.

Great thoughts about thyroid, JoAnn. She has an under active thyroid and is on levothyroxine, but maybe it’s time to get the blood level checked. I’m sure the dementia doesn’t help, but I had not considered the thyroid.
Blessings!

Of what does her diet consist?  Is she able to eat good healthy foods?  This may seem rather simple, but I've found that it makes such a difference.   I'm often chilled until I eat, then I can feel the warmth from the food as it's "processing."

If she's not restricted in her diet, you might consider something like heated cider.   It doesn't have the array of ingredients that hot chocolate does (unless you make it from scratch, which we did before it was available in packages).   Herbal teas could help as well, as do good hearty soups.

Not to be personal or blunt, but what kind of underwear does she use?   Some of the fancy nylons aren't very warm, nor are some of the cheap cotton underwear products.  

I also double up, wearing either a sweatshirt or t-shirt underneath another sweatshirt.   During really cold winters, I also wore either 2 pairs of sweat pants, or leotards underneath sweat pants.   Surprisingly, the leotards kept me warm.

Another thing I wear is dancer's leg warmers, worn over the sweat pants.  These are especially warming on cold winter days when snow shoveling is on the agenda.  I also wear men's hunting socks.  They're so superior to the mass produced women's socks.

Does she exercise, or walk around, just to generate energy?

Yes, it is her blood circulation. When it isn't circulating enough, then the warmth of the blood does not get into her hands and feet, and particularly her chest. I don't know how to help her because I am 75 years old on Nov. 27th and have just realized that when I checked the weather reports and it said 75 to 80 degrees, my first impression was, "Oh, it will be cold out today!" I never would have thought that when younger. All I can say is turn up the heater to 80 to 85 degrees and see if that helps. If you can't stand the same temp, you guys may have to start sleeping in different rooms. Have you tried a heated blanket? Amazon also has heated gloves.

Alpaca socks for women are very warm and very soft. Bought some for my mom who is always cold too and I got some for myself to try them. They are my go-to socks in the winter.

And yes, the head. I forgot that I now have to wear a winter cap on my head or I'm not able to sleep. There are also fleece lined socks and fleece lined slippers.
Doesn't she have one of those devices that help a person put on their own socks? I have one. It is plastic with two cords attached. You put the sock on the plastic, and pull it on with the two cords.

https://seniorsafetyadvice.com/are-electric-blankets-safe-for-elderly/

My mother was always freezing to the point of shaking. We bought her Cuddle Duds to wear under her clothes, alpaca-knit fingerless gloves to wear in the house and lots of sherpa fleece. She also loved those packs that you put in the microwave to heat up.

Asfor the reason why, it could be a million things. My mom was severely anemic and had advanced kidney disease, both of which plaited into this.

Like Monkeymama, my mom had kidney problems.

I got her a beautiful washable lightweight down winter coat. She wore it year round.

I kept shawls in the trunk so she could have an extra wrap (or three) whenever she felt cold.

Her favorite things were electric blankets and we had multiple- one on her bed (along with an electric heated mattress pad) and electric throws wherever she liked to sit. Our favorite brand was Brookstone and I noticed they now sell at Costco. If you cover them with another blanket while “preheating” they are significantly more effective.

They don’t survive many washes.

The biggest problem may be getting her out of her cozy bed.

Look for lightweight undergarments like silk or polypropelene worn for camping and outdoor activities. They provide a comfortable layer of insulation without being too heavy or hot for indoors.

The only thing about heating pads, is they have to be heated constantly. Not only that, but they can cause Erythema Ab Igne,
which leaves deep dark red marks on the skin and take forever to fade. Maybe try a nice soft warm hat. They sell them on amazon.

Help her to take a warm/hot shower
or bath that will warm her up.
Then she can apply the heating appliance you are getting her. Also
make sure she has socks on.

Get her a mattress pad that heats up
You apply the mattress pad to the mattress and it has to be plugged in
but I have found they are great for keeping warm

Caps and wool socks.

My dad had to wear a stocking cap all the time, summer or winter. Keeping his head warm helped. Also before I’d give him his shower I’d take a small portable heater into the bathroom and get it really warm in there before it was time to undress. These things helped him not be as chilled.

Many if not most people with an underactive thyroid feel cold all the time, even on a hot July day. These are the people who wear a sweater when other people are wearing shorts! If your doctor hasn't had her take a thyroid test for quite a while, schedule an appointment right away.

Yes--the body's ability to regulate temperature can decline with age. Temperature regulation can be affected by the dementias as well.
A 'Yes!' vote for hats and a thyroid level check. You can find inexpensive, lightweight fleece caps at any Target, TJ Maxx, etc. (basically a tube with an end sewn shut). They are easy to launder and not bulky.
I'm a fan of those quilted or polar fleece vests under whatever outer layers are in use.
I have a heated mattress pad that has separate controls for each side of the bed--it's nice to get into a warm bed as it gets colder.

Seniors get cold!
You should keep the temp at least 76 degrees.
Let her wear 100% soft cotton insulated long sleeve top and bottoms with a warm flannel night gown on top.

Not a good idea to use heating pads because of burns but you have the best idea already about letting her have an electric blanket to keep warm with.

I believe they also sell blankets with holes for your arms to stick out.

Remember that a nice soft non tight hat will keep the warmth of her body in and nice soft bootie like socks will also keep the warmth in her body.

You can also keep a thermos close by that has warm tea as the fluids will be good for her.

Read side effects of meds. That may be the problem.

My husband has A. D. and often feels cold.
His doctor said that since the brain is dying (and the hypothalamus, temp controller, is in the brain) temperature control is not working properly.

Could be as simple as a result of taking anti-histamines, or it could be blood pressure related.
Get a full check-up. Go to a gym with a hot tub perhaps.
Best wishes.

Try peel and stick toe warmers (they stick to the bottom of the foot over the sock ) Some brands get pretty hot, others not so much, but when someone is very cold, warming up the feet warms the whole body. Toe warmers can be expensive if used a lot- 50 cents to one dollar for each use which lasts 4-8 hours. Hot hands toe warmers get pretty hot but Little Hotties brand and Grabber brand don't get as hot. Most people use them when they are going to be outside in the cold for an extended time. Anyone who dreads going outside in the cold to go for a walk should try them.

Ask the dr if there is indications in labwork that would cause cold all the time. Then ask pharmacist if any meds might cause it. Other than that, some folks are just cold and get colder the older they get. Often home health people or those who do home visits, find elderly with heat on when it is very hot outside. They nearly pass out from heat while the elderly person is still complaining of the cold. If there is a heat duct near her, put a directional cover on it to direct the heat to her. That can help. They make smaller heated throws to cover with. Buy her only winter clothes.

I'm a cold all the time and used to keep a heated throw in my chair at work. For the life of me, I never understood why all those hot-natured women in the office had to run out and buy new winter clothes to be fashionable when they should have been buying summer clothes year round. It was a constant battle at the thermostat!

Put her blanket, sweater, pants, socks— whatever she is wearing in the dryer for a warm up and then put them on her. She will love it.
also- an excellent thing to do with towels after bathing.

One of the biggest side effects from chemo was how bloody cold I was...always! I wore a knit cap, even at night...maybe especially at night. I had warm fuzzy mittens, a heated blankie that was split half way up so I could have it up and over each shoulder, and down my lap. I wore one pair of leggings under regular pants, and a mens tee shirt under a sweater. Flannel p.j.'s, and used flannel sheets. This was in July and August. Wish I would have thought about the mens hunting sox!

I only use plush blankets for my mom. They are very warm and lightweight. She likes two or three at a time and loves how soft and cozy they are. I also bought a small hot water bottle with a pretty cover on Amazon to hold on her lap and found that if her hands are warm she feels warm all over.

One thing I learned from living in a cold climate for a while was that if you can't keep your core warm, the rest of you won't be warm either. I learned to hold something warm against my lower abdomen or between my thighs in bed, and I'd get warm immediately. Try a hot water bottle or a heating pad on low in those areas.

During the coldest Colorado days, I often used those ThermaCare pads meant for sore muscles, and I'd stick one on my abdomen or high on my inner thigh to warm my femoral artery area. It worked like a charm and they stay warm for 12 hours. It's not a cheap alternative, but when you're really freezing, they're great.

Definitely ask her doctor if those are safe for her to use, though. They get pretty warm, and I wouldn't want her skin to be damaged.

Has her thyroid been checked? My mom's was out of whack and it caused her to be freezing all the time. Now that it is regulated again she isn't experiencing being cold all the time. All the best to you and your wife.

There could be several medical reasons - anemic, hypothyroidism and other things I'm sure I'm not aware of. Both of those I mentioned could be shown in bloodwork. Maybe mention it to her doctor so they can run some routine bloodwork.

Depending on her age, alot of older people are cold all the time. It could be from routine things that just happen as we age - diminished circulation. Also loss of muscle and body fat, slower metabolism or the inability to move fast enough to generate heat.